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Int. J. Mol. Sci., Volume 13, Issue 3 (March 2012) – 86 articles , Pages 2535-4002

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Article
Dihydrolipoic Acid Induces Cytotoxicity in Mouse Blastocysts through Apoptosis Processes
Int. J. Mol. Sci. 2012, 13(3), 3988-4002; https://doi.org/10.3390/ijms13033988 - 22 Mar 2012
Cited by 5 | Viewed by 4075
Abstract
α-Lipoic acid (LA) is a thiol with antioxidant properties that protects against oxidative stress-induced apoptosis. LA is absorbed from the diet, taken up by cells and tissues, and subsequently reduced to dihydrolipoic acid (DHLA). In view of the recent application of DHLA as [...] Read more.
α-Lipoic acid (LA) is a thiol with antioxidant properties that protects against oxidative stress-induced apoptosis. LA is absorbed from the diet, taken up by cells and tissues, and subsequently reduced to dihydrolipoic acid (DHLA). In view of the recent application of DHLA as a hydrophilic nanomaterial preparation, determination of its biosafety profile is essential. In the current study, we examined the cytotoxic effects of DHLA on mouse embryos at the blastocyst stage, subsequent embryonic attachment and outgrowth in vitro, in vivo implantation by embryo transfer, and early embryonic development in an animal model. Blastocysts treated with 50 μM DHLA exhibited significantly increased apoptosis and a corresponding decrease in total cell number. Notably, the implantation success rates of blastocysts pretreated with DHLA were lower than that of their control counterparts. Moreover, in vitro treatment with 50 μM DHLA was associated with increased resorption of post-implantation embryos and decreased fetal weight. Data obtained using an in vivo mouse model further disclosed that consumption of drinking water containing 100 μM DHLA led to decreased early embryo development, specifically, inhibition of development to the blastocyst stage. However, it appears that concentrations of DHLA lower than 50 μM do not exert a hazardous effect on embryonic development. Our results collectively indicate that in vitro and in vivo exposure to concentrations of DHLA higher than 50 μM DHLA induces apoptosis and retards early pre- and post-implantation development, and support the potential of DHLA to induce embryonic cytotoxicity. Full article
(This article belongs to the Section Molecular Toxicology)
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Article
Therapeutic Effect of Arsenicum album on Leukocytes
Int. J. Mol. Sci. 2012, 13(3), 3979-3987; https://doi.org/10.3390/ijms13033979 - 22 Mar 2012
Cited by 9 | Viewed by 7092
Abstract
The therapeutic effects of homoeopathic Arsenicum album potencies were investigated in-vitro, using a continuous cell line (MT4), pre-intoxicated with arsenic trioxide (As2O3), and then treated with succussed and unsuccussed homoeopathic potencies, 6CH, 30CH and 200CH. This study aimed [...] Read more.
The therapeutic effects of homoeopathic Arsenicum album potencies were investigated in-vitro, using a continuous cell line (MT4), pre-intoxicated with arsenic trioxide (As2O3), and then treated with succussed and unsuccussed homoeopathic potencies, 6CH, 30CH and 200CH. This study aimed to verify the homoeopathic law of similars and to determine whether potencies diluted beyond Avogadro’s constant had physiological effects on cells; whether various potencies would cause different effects as suggested by the concept of hormesis; whether succussed and unsuccussed homoeopathic potencies had different effects on the cells; and to establish whether a biotechnological method could be used to evaluate the above. As2O3 was used to pre-intoxicate and the MTT assay was used to measure the percentage cytotoxicity and half maximal inhibitory concentration (IC50) of the cells. The homoeopathic potencies of Arsenicum album (6CH, 30CH and 200CH) were prepared by either succussing or allowing to diffuse for 30 s. After pre-intoxication of the MT4 cells with the IC50 As2O3 and treatment with succussed and unsuccussed Arsenicum album (6CH-200CH), the cell viability increased with increasing potency from 81% to 194% (over 72 h). The treatments and the times of exposure were found to be statistically significant determinants of cell viability, whereas succussion did not cause any significant variation in the results. The study provided evidence that a biotechnological method (namely cell viability) may be used to scientifically evaluate the physiological effects of homoeopathic potencies on human cells; it confirmed that the homoeopathic potencies did have therapeutic effects; and that succussion was not required in the potentization method in order to produce a curative remedy. Full article
(This article belongs to the Section Molecular Toxicology)
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Review
Curcumin: Updated Molecular Mechanisms and Intervention Targets in Human Lung Cancer
Int. J. Mol. Sci. 2012, 13(3), 3959-3978; https://doi.org/10.3390/ijms13033959 - 22 Mar 2012
Cited by 69 | Viewed by 10237
Abstract
Curcumin, a yellow pigment derived from Curcuma longa Linn, has attracted great interest in the research of cancer during the past decades. Extensive studies documented that curcumin attenuates cancer cell proliferation and promotes apoptosis in vivo and in vitro. Curcumin has [...] Read more.
Curcumin, a yellow pigment derived from Curcuma longa Linn, has attracted great interest in the research of cancer during the past decades. Extensive studies documented that curcumin attenuates cancer cell proliferation and promotes apoptosis in vivo and in vitro. Curcumin has been demonstrated to interact with multiple molecules and signal pathways, which makes it a potential adjuvant anti-cancer agent to chemotherapy. Previous investigations focus on the mechanisms of action for curcumin, which is shown to manipulate transcription factors and induce apoptosis in various kinds of human cancer. Apart from transcription factors and apoptosis, emerging studies shed light on latent targets of curcumin against epidermal growth factor receptor (EGFR), microRNAs (miRNA), autophagy and cancer stem cell. The present review predominantly discusses significance of EGFR, miRNA, autophagy and cancer stem cell in lung cancer therapy. Curcumin as a natural phytochemicals could communicate with these novel targets and show synergism to chemotherapy. Additionally, curcumin is well tolerated in humans. Therefore, EGFR-, miRNA-, autophagy- and cancer stem cell-based therapy in the presence of curcumin might be promising mechanisms and targets in the therapeutic strategy of lung cancer. Full article
(This article belongs to the Section Biochemistry)
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Article
Cooperative Modulation of Mineral Growth by Prismatic-Associated Asprich Sequences and Mg(II)
Int. J. Mol. Sci. 2012, 13(3), 3949-3958; https://doi.org/10.3390/ijms13033949 - 22 Mar 2012
Cited by 13 | Viewed by 3518
Abstract
Cooperative effects of magnesium ions and acidic polypeptides originating from a family of proteins known as Asprich (mollusk Atrina rigida) were studied. In our previous studies, these two acidic polypeptides were found to be effective in controlling the morphology of the calcium [...] Read more.
Cooperative effects of magnesium ions and acidic polypeptides originating from a family of proteins known as Asprich (mollusk Atrina rigida) were studied. In our previous studies, these two acidic polypeptides were found to be effective in controlling the morphology of the calcium carbonate mineral, the main inorganic constituent of prismatic layer of the mollusk shell. Since these Asprich sequences are believed to contain a putative magnesium binding domain, the morphology-controlling effects were further investigated with the addition of magnesium ions. The mineral morphology was dramatically changed by the combined influence of each polypeptides and the magnesium ions, substantiating the recognized importance of magnesium in the formation of calcium carbonate-based biominerals. Full article
(This article belongs to the Special Issue Composite Materials in Skeletal Engineering)
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Article
A Single-Chamber Microbial Fuel Cell without an Air Cathode
Int. J. Mol. Sci. 2012, 13(3), 3933-3948; https://doi.org/10.3390/ijms13033933 - 22 Mar 2012
Cited by 35 | Viewed by 5091
Abstract
Microbial fuel cells (MFCs) represent a novel technology for wastewater treatment with electricity production. Electricity generation with simultaneous nitrate reduction in a single-chamber MFC without air cathode was studied, using glucose (1 mM) as the carbon source and nitrate (1 mM) as the [...] Read more.
Microbial fuel cells (MFCs) represent a novel technology for wastewater treatment with electricity production. Electricity generation with simultaneous nitrate reduction in a single-chamber MFC without air cathode was studied, using glucose (1 mM) as the carbon source and nitrate (1 mM) as the final electron acceptor employed by Bacillus subtilis under anaerobic conditions. Increasing current as a function of decreased nitrate concentration and an increase in biomass were observed with a maximum current of 0.4 mA obtained at an external resistance (Rext) of 1 KΩ without a platinum catalyst of air cathode. A decreased current with complete nitrate reduction, with further recovery of the current immediately after nitrate addition, indicated the dependence of B. subtilis on nitrate as an electron acceptor to efficiently produce electricity. A power density of 0.0019 mW/cm2 was achieved at an Rext of 220 Ω. Cyclic voltammograms (CV) showed direct electron transfer with the involvement of mediators in the MFC. The low coulombic efficiency (CE) of 11% was mainly attributed to glucose fermentation. These results demonstrated that electricity generation is possible from wastewater containing nitrate, and this represents an alternative technology for the cost-effective and environmentally benign treatment of wastewater. Full article
(This article belongs to the Section Green Chemistry)
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Article
Enhancement of Biocontrol Efficacy of Pichia carribbica to Postharvest Diseases of Strawberries by Addition of Trehalose to the Growth Medium
Int. J. Mol. Sci. 2012, 13(3), 3916-3932; https://doi.org/10.3390/ijms13033916 - 22 Mar 2012
Cited by 29 | Viewed by 4307
Abstract
The effects of trehalose on the antagonistic activity of Pichia caribbica against Rhizopus decay and gray mold decay of strawberries and the possible mechanisms involved were investigated. The proteomic analysis and comparison of P. carribbica in response to trehalose was analyzed based on [...] Read more.
The effects of trehalose on the antagonistic activity of Pichia caribbica against Rhizopus decay and gray mold decay of strawberries and the possible mechanisms involved were investigated. The proteomic analysis and comparison of P. carribbica in response to trehalose was analyzed based on two-dimensional gel electrophoresis. The antagonistic activity of P. carribbica harvested from the culture media of NYDB amended with trehalose at 0.5% was improved greatly compared with that without trehalose. The PPO (Polyphenoloxidase) and POD (Peroxidase) activity of strawberries treated with P. carribbica cultured in the NYDB media amended with trehalose at 0.5% was higher than that of the strawberries treated with P. carribbica harvested from NYDB. The β-1, 3-glucanase activity of strawberries treated with P. carribbica cultured in the NYDB media amended with trehalose at 0.5% was also higher than that of the strawberries treated with P. carribbica harvested from NYDB and the control. Several differentially expressed proteins of P. carribbica in response to trehalose were identified in the cellular proteome, most of them were related to basic metabolism. Full article
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Article
Genetic Diversity of the Endemic and Medicinally Important Plant Rheum officinale as Revealed by Inter-Simpe Sequence Repeat (ISSR) Markers
Int. J. Mol. Sci. 2012, 13(3), 3900-3915; https://doi.org/10.3390/ijms13033900 - 22 Mar 2012
Cited by 47 | Viewed by 4762
Abstract
Rheum officinale Baill., an important but endangered medicinal herb, is endemic to China. Inter-simple sequence repeat (ISSR) markers were employed to investigate the genetic diversity and differentiation of 12 populations of R. officinale. Thirteen selected primers yielded 189 bright and discernible bands, [...] Read more.
Rheum officinale Baill., an important but endangered medicinal herb, is endemic to China. Inter-simple sequence repeat (ISSR) markers were employed to investigate the genetic diversity and differentiation of 12 populations of R. officinale. Thirteen selected primers yielded 189 bright and discernible bands, with an average of 14.54 per primer. The genetic diversity was low at the population level, but pretty high at the species level (H = 0.1008, I = 0.1505, PPB = 28.95% vs. H = 0.3341, I = 0.5000, PPB = 95.24%, respectively) by POPGENE analysis. Analysis of molecular variance (AMOVA) showed that the genetic variation was found mainly among populations (74.38%), in line with the limited gene flow (Nm = 0.2766) among populations. Mantel test revealed a significant correlation between genetic and geographic distances (r = 0.5381, P = 0.002), indicating the role of geographic isolation in shaping the present population genetic structure. Both Bayesian analysis and UPGMA cluster analysis demonstrated the similar results. Our results imply that the conservation efforts should aim to preserve all the extant populations of this endangered species, and cultivation is proposed in this study. Full article
(This article belongs to the Special Issue Advances in Molecular Plant Biology)
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Article
Antinociceptive and Anti-Inflammatory Effects of Ethanol Extract from Vernonia polyanthes Leaves in Rodents
Int. J. Mol. Sci. 2012, 13(3), 3887-3899; https://doi.org/10.3390/ijms13033887 - 22 Mar 2012
Cited by 23 | Viewed by 4682
Abstract
The ethanol extract from Vernonia polyanthes leaves (EEVP) was investigated for antinociceptive and anti-inflammatory effects at the doses (p.o.) of 100, 200 and 400 mg/kg in animal models. The extract reduced the number of abdominal contortions by 16.75% and 31.44% at a dose [...] Read more.
The ethanol extract from Vernonia polyanthes leaves (EEVP) was investigated for antinociceptive and anti-inflammatory effects at the doses (p.o.) of 100, 200 and 400 mg/kg in animal models. The extract reduced the number of abdominal contortions by 16.75% and 31.44% at a dose of 200 and 400 mg/kg, respectively. The results obtained showed that EEVP exerted a significant antinociceptive effect in the two phases of formalin. The EEVP increased the reaction time on a hot plate at the doses of 100, 200 and 400 mg/kg after 90 min of treatment. The paw edema was reduced by EEVP at the doses of 100, 200 and 400 mg/kg after 4 h of application of carrageenan. Doses of 200 and 400 mg/kg, administered 4 h before the carrageenan injection, significantly reduced the exudate volume (29.25 and 45.74%, respectively) and leukocyte migration (18.19 and 27.95%, respectively). These results suggest that V. polyanthes can be an active source of substances with antinociceptive and anti-inflammatory activities. Full article
(This article belongs to the Section Biochemistry)
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Review
Functionalized Nanostructures with Application in Regenerative Medicine
Int. J. Mol. Sci. 2012, 13(3), 3847-3886; https://doi.org/10.3390/ijms13033847 - 22 Mar 2012
Cited by 69 | Viewed by 8479
Abstract
In the last decade, both regenerative medicine and nanotechnology have been broadly developed leading important advances in biomedical research as well as in clinical practice. The manipulation on the molecular level and the use of several functionalized nanoscaled materials has application in various [...] Read more.
In the last decade, both regenerative medicine and nanotechnology have been broadly developed leading important advances in biomedical research as well as in clinical practice. The manipulation on the molecular level and the use of several functionalized nanoscaled materials has application in various fields of regenerative medicine including tissue engineering, cell therapy, diagnosis and drug and gene delivery. The themes covered in this review include nanoparticle systems for tracking transplanted stem cells, self-assembling peptides, nanoparticles for gene delivery into stem cells and biomimetic scaffolds useful for 2D and 3D tissue cell cultures, transplantation and clinical application. Full article
(This article belongs to the Special Issue From Molecules to Nanomaterials)
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Review
Inroads to Predict in Vivo Toxicology—An Introduction to the eTOX Project
Int. J. Mol. Sci. 2012, 13(3), 3820-3846; https://doi.org/10.3390/ijms13033820 - 21 Mar 2012
Cited by 50 | Viewed by 9501
Abstract
There is a widespread awareness that the wealth of preclinical toxicity data that the pharmaceutical industry has generated in recent decades is not exploited as efficiently as it could be. Enhanced data availability for compound comparison (“read-across”), or for data mining to build [...] Read more.
There is a widespread awareness that the wealth of preclinical toxicity data that the pharmaceutical industry has generated in recent decades is not exploited as efficiently as it could be. Enhanced data availability for compound comparison (“read-across”), or for data mining to build predictive tools, should lead to a more efficient drug development process and contribute to the reduction of animal use (3Rs principle). In order to achieve these goals, a consortium approach, grouping numbers of relevant partners, is required. The eTOX (“electronic toxicity”) consortium represents such a project and is a public-private partnership within the framework of the European Innovative Medicines Initiative (IMI). The project aims at the development of in silico prediction systems for organ and in vivo toxicity. The backbone of the project will be a database consisting of preclinical toxicity data for drug compounds or candidates extracted from previously unpublished, legacy reports from thirteen European and European operation-based pharmaceutical companies. The database will be enhanced by incorporation of publically available, high quality toxicology data. Seven academic institutes and five small-to-medium size enterprises (SMEs) contribute with their expertise in data gathering, database curation, data mining, chemoinformatics and predictive systems development. The outcome of the project will be a predictive system contributing to early potential hazard identification and risk assessment during the drug development process. The concept and strategy of the eTOX project is described here, together with current achievements and future deliverables. Full article
(This article belongs to the Special Issue Advances in Computational Toxicology)
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Article
The Effect of Osmolytes on Protein Fibrillation
Int. J. Mol. Sci. 2012, 13(3), 3801-3819; https://doi.org/10.3390/ijms13033801 - 21 Mar 2012
Cited by 56 | Viewed by 5356
Abstract
Osmolytes are small molecules that are exploited by cells as a protective system against stress conditions. They favour compact protein states which makes them stabilize globular proteins in vitro and promote folding. Conversely, this preference for compact states promotes aggregation of unstructured proteins. [...] Read more.
Osmolytes are small molecules that are exploited by cells as a protective system against stress conditions. They favour compact protein states which makes them stabilize globular proteins in vitro and promote folding. Conversely, this preference for compact states promotes aggregation of unstructured proteins. Here we combine a brief review of the effect of osmolytes on protein fibrillation with a report of the effect of osmolytes on the unstructured peptide hormone glucagon. Our results show that osmolytes either accelerate the fibrillation kinetics or leave them unaffected, with the exception of the osmolyte taurine. Furthermore, the osmolytes that affected the shape of the fibrillation time profile led to fibrils with different structure as revealed by CD. The structural changes induced by Pro, Ser and choline-O-sulfate could be due to specific osmolytes binding to the peptides, stabilizing an otherwise labile fibrillation intermediate. Full article
(This article belongs to the Special Issue Protein Aggregation)
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Communication
Increasing the X-ray Diffraction Power of Protein Crystals by Dehydration: The Case of Bovine Serum Albumin and a Survey of Literature Data
Int. J. Mol. Sci. 2012, 13(3), 3782-3800; https://doi.org/10.3390/ijms13033782 - 21 Mar 2012
Cited by 40 | Viewed by 5147
Abstract
Serum albumin is one of the most widely studied proteins. It is the most abundant protein in plasma with a typical concentration of 5 g/100 mL and the principal transporter of fatty acids in plasma. While the crystal structures of human serum albumin [...] Read more.
Serum albumin is one of the most widely studied proteins. It is the most abundant protein in plasma with a typical concentration of 5 g/100 mL and the principal transporter of fatty acids in plasma. While the crystal structures of human serum albumin (HSA) free and in complex with fatty acids, hemin, and local anesthetics have been characterized, no crystallographic models are available on bovine serum albumin (BSA), presumably because of the poor diffraction power of existing hexagonal BSA crystals. Here, the crystallization and diffraction data of a new BSA crystal form, obtained by the hanging drop method using MPEG 5K as precipitating agent, are presented. The crystals belong to space group C2, with unit-cell parameters a = 216.45 Å, b = 44.72 Å, c = 140.18 Å, β = 114.5°. Dehydration was found to increase the diffraction limit of BSA crystals from ~8 Å to 3.2 Å, probably by improving the packing of protein molecules in the crystal lattice. These results, together with a survey of more than 60 successful cases of protein crystal dehydration, confirm that it can be a useful procedure to be used in initial screening as a method of improving the diffraction limits of existing crystals. Full article
(This article belongs to the Section Biochemistry)
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Review
Recent Advances of Flowering Locus T Gene in Higher Plants
Int. J. Mol. Sci. 2012, 13(3), 3773-3781; https://doi.org/10.3390/ijms13033773 - 21 Mar 2012
Cited by 20 | Viewed by 4622
Abstract
Flowering Locus T (FT) can promote flowering in the plant photoperiod pathway and also facilitates vernalization flowering pathways and other ways to promote flowering. The expression of products of the FT gene is recognized as important parts of the flowering hormone [...] Read more.
Flowering Locus T (FT) can promote flowering in the plant photoperiod pathway and also facilitates vernalization flowering pathways and other ways to promote flowering. The expression of products of the FT gene is recognized as important parts of the flowering hormone and can induce flowering by long-distance transportation. In the present study, many FT-like genes were isolated, and the transgenic results show that FT gene can promote flowering in plants. This paper reviews the progress of the FT gene and its expression products to provide meaningful information for further studies of the functions of FT genes. Full article
(This article belongs to the Special Issue Advances in Molecular Plant Biology)
Communication
Production of Protocatechuic Acid in Bacillus Thuringiensis ATCC33679
Int. J. Mol. Sci. 2012, 13(3), 3765-3772; https://doi.org/10.3390/ijms13033765 - 21 Mar 2012
Cited by 27 | Viewed by 4139
Abstract
Protocatechuic acid, or 3,4-dihydroxybenzoic acid, is produced by both soil and marine bacteria in the free form and as the iron binding component of the siderophore petrobactin. The soil bacterium, Bacillus thuringiensis kurstaki ATCC 33679, contains the asb operon, but does not produce [...] Read more.
Protocatechuic acid, or 3,4-dihydroxybenzoic acid, is produced by both soil and marine bacteria in the free form and as the iron binding component of the siderophore petrobactin. The soil bacterium, Bacillus thuringiensis kurstaki ATCC 33679, contains the asb operon, but does not produce petrobactin. Iron restriction resulted in diminished B. thuringiensis kurstaki ATCC 33679 growth and the production of catechol(s). The gene product responsible for protocatechuic acid (asbF) and its receptor (fatB) were expressed during stationary phase growth. Gene expression varied with growth temperature, with optimum levels occurring well below the Bacillus anthracis virulence temperature of 37 °C. Regulation of protocatechuic acid suggests a possible role for this compound during soil growth cycles. Full article
(This article belongs to the Section Biochemistry)
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Article
Expression Analysis of Four Peroxiredoxin Genes from Tamarix hispida in Response to Different Abiotic Stresses and Exogenous Abscisic Acid (ABA)
Int. J. Mol. Sci. 2012, 13(3), 3751-3764; https://doi.org/10.3390/ijms13033751 - 21 Mar 2012
Cited by 16 | Viewed by 3970
Abstract
Peroxiredoxins (Prxs) are a recently discovered family of antioxidant enzymes that catalyze the reduction of peroxides and alkyl peroxides. In this study, four Prx genes (named as ThPrxII, ThPrxIIE, ThPrxIIF, and Th2CysPrx) were cloned from Tamarix hispida. Their [...] Read more.
Peroxiredoxins (Prxs) are a recently discovered family of antioxidant enzymes that catalyze the reduction of peroxides and alkyl peroxides. In this study, four Prx genes (named as ThPrxII, ThPrxIIE, ThPrxIIF, and Th2CysPrx) were cloned from Tamarix hispida. Their expression profiles in response to stimulus of NaCl, NaHCO3, PEG, CdCl2 and abscisic acid (ABA) in roots, stems and leaves of T. hispida were investigated using real-time RT-PCR. The results showed that the four ThPrxs were all expressed in roots, stems and leaves. Furthermore, the transcript levels of ThPrxIIE and ThPrxII were the lowest and the highest, respectively, in all tissue types. All the ThPrx genes were induced by both NaCl and NaHCO3 and reached their highest expression levels at the onset of stress in roots. Under PEG and CdCl2 stress, the expression patterns of these ThPrxs showed temporal and spatial specificity. The expressions of the ThPrxs were all differentially regulated by ABA, indicating that they are all involved in the ABA signaling pathway. These findings reveal a complex regulation of Prxs that is dependent on the type of Prx, tissue, and the signaling molecule. The divergence of the stress-dependent transcriptional regulation of the ThPrx gene family in T. hispida may provide an essential basis for the elucidation of Prx function in future work. Full article
(This article belongs to the Special Issue Advances in Molecular Plant Biology)
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Article
Antihyperglycemic and Antioxidative Effects of Hydroxyethyl Methylcellulose (HEMC) and Hydroxypropyl Methylcellulose (HPMC) in Mice Fed with a High Fat Diet
Int. J. Mol. Sci. 2012, 13(3), 3738-3750; https://doi.org/10.3390/ijms13033738 - 21 Mar 2012
Cited by 10 | Viewed by 3751
Abstract
The effect of dietary feeding of hydroxyethyl methylcellulose (HEMC) and hydroxypropyl methylcellulose (HPMC) on the glucose metabolism and antioxidative status in mice under high fat diet conditions was investigated. The mice were randomly divided and given experimental diets for six weeks: normal control [...] Read more.
The effect of dietary feeding of hydroxyethyl methylcellulose (HEMC) and hydroxypropyl methylcellulose (HPMC) on the glucose metabolism and antioxidative status in mice under high fat diet conditions was investigated. The mice were randomly divided and given experimental diets for six weeks: normal control (NC group), high fat (HF group), and high fat supplemented with either HEMC (HF+HEMC group) or HPMC (HF+HPMC group). At the end of the experimental period, the HF group exhibited markedly higher blood glucose and insulin levels as well as a higher erythrocyte lipid peroxidation rate relative to the control group. However, diet supplementation of HEMC and HPMC was found to counteract the high fat-induced hyperglycemia and oxidative stress via regulation of antioxidant and hepatic glucose-regulating enzyme activities. These findings illustrate that HEMC and HPMC were similarly effective in improving the glucose metabolism and antioxidant defense system in high fat-fed mice and they may be beneficial as functional biomaterials in the development of therapeutic agents against high fat diet-induced hyperglycemia and oxidative stress. Full article
(This article belongs to the Section Biochemistry)
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Article
Photosensized Controlling Benzyl Methacrylate-Based Matrix Enhanced Eu3+ Narrow-Band Emission for Fluorescence Applications
Int. J. Mol. Sci. 2012, 13(3), 3718-3737; https://doi.org/10.3390/ijms13033718 - 21 Mar 2012
Cited by 4 | Viewed by 4247
Abstract
This study synthesized a europium (Eu3+) complex Eu(DBM)3Cl-MIP (DBM = dibenzoyl methane; Cl-MIP = 2-(2-chlorophenyl)-1-methyl-1H-imidazo[4,5-f][1,10]phenanthroline) dispersed in a benzyl methacrylate (BMA) monomer and treated with ultraviolet (UV) light for polymerization. Spectral results showed that the europium complex [...] Read more.
This study synthesized a europium (Eu3+) complex Eu(DBM)3Cl-MIP (DBM = dibenzoyl methane; Cl-MIP = 2-(2-chlorophenyl)-1-methyl-1H-imidazo[4,5-f][1,10]phenanthroline) dispersed in a benzyl methacrylate (BMA) monomer and treated with ultraviolet (UV) light for polymerization. Spectral results showed that the europium complex containing an antenna, Cl-MIP, which had higher triplet energy into the Eu3+ energy level, was an energetically enhanced europium emission. Typical stacking behaviors of π–π interactions between the ligands and the Eu3+-ion were analyzed using single crystal X-ray diffraction. Regarding the luminescence performance of this europium composite, the ligand/defect emission was suppressed by dispersion in a poly-BMA (PBMA) matrix. The underlying mechanism of the effective enhancement of the pure Eu3+ emission was attributed to the combined effects of structural modifications, defect emissions, and carrier charge transfer. Fluorescence spectra were compared to the composite of optimized Eu3+ emission where they were subsequently chelated to four metal ions via carboxylate groups on the BMA unit. The optical enhanced europium composite clearly demonstrated highly efficient optical responses and is, therefore a promising application as an optical detection material. Full article
(This article belongs to the Special Issue Correlation Analysis Applied to Solvolysis Reactions)
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Article
Effect of Polyethylene Glycol Modification of TiO2 Nanoparticles on Cytotoxicity and Gene Expressions in Human Cell Lines
Int. J. Mol. Sci. 2012, 13(3), 3703-3717; https://doi.org/10.3390/ijms13033703 - 21 Mar 2012
Cited by 61 | Viewed by 6895
Abstract
Nanoparticles (NPs) are tiny materials used in a wide range of industrial and medical applications. Titanium dioxide (TiO2) is a type of nanoparticle that is widely used in paints, pigments, and cosmetics; however, little is known about the impact of TiO [...] Read more.
Nanoparticles (NPs) are tiny materials used in a wide range of industrial and medical applications. Titanium dioxide (TiO2) is a type of nanoparticle that is widely used in paints, pigments, and cosmetics; however, little is known about the impact of TiO2 on human health and the environment. Therefore, considerable research has focused on characterizing the potential toxicity of nanoparticles such as TiO2 and on understanding the mechanism of TiO2 NP-induced nanotoxicity through the evaluation of biomarkers. Uncoated TiO2 NPs tend to aggregate in aqueous media, and these aggregates decrease cell viability and induce expression of stress-related genes, such as those encoding interleukin-6 (IL-6) and heat shock protein 70B’ (HSP70B’), indicating that TiO2 NPs induce inflammatory and heat shock responses. In order to reduce their toxicity, we conjugated TiO2 NPs with polyethylene glycol (PEG) to eliminate aggregation. Our findings indicate that modifying TiO2 NPs with PEG reduces their cytotoxicity and reduces the induction of stress-related genes. Our results also suggest that TiO2 NP-induced effects on cytotoxicity and gene expression vary depending upon the cell type and surface modification. Full article
(This article belongs to the Special Issue Nanotoxicology)
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Article
Cellulose Biosynthesis Inhibitors: Comparative Effect on Bean Cell Cultures
Int. J. Mol. Sci. 2012, 13(3), 3685-3702; https://doi.org/10.3390/ijms13033685 - 20 Mar 2012
Cited by 12 | Viewed by 3934
Abstract
The variety of bioassays developed to evaluate different inhibition responses for cellulose biosynthesis inhibitors makes it difficult to compare the results obtained. This work aims (i) to test a single inhibitory assay for comparing active concentrations of a set of putative cellulose biosynthesis [...] Read more.
The variety of bioassays developed to evaluate different inhibition responses for cellulose biosynthesis inhibitors makes it difficult to compare the results obtained. This work aims (i) to test a single inhibitory assay for comparing active concentrations of a set of putative cellulose biosynthesis inhibitors and (ii) to characterize their effect on cell wall polysaccharides biosynthesis following a short-term exposure. For the first aim, dose-response curves for inhibition of dry-weight increase following a 30 days exposure of bean callus-cultured cells to these inhibitors were obtained. The compound concentration capable of inhibiting dry weight increase by 50% compared to control (I50) ranged from subnanomolar (CGA 325′615) to nanomolar (AE F150944, flupoxam, triazofenamide and oxaziclomefone) and micromolar (dichlobenil, quinclorac and compound 1) concentrations. In order to gain a better understanding of the effect of the putative inhibitors on cell wall polysaccharides biosynthesis, the [14C]glucose incorporation into cell wall fractions was determined after a 20 h exposure of cell suspensions to each inhibitor at their I50 value. All the inhibitors tested decreased glucose incorporation into cellulose with the exception of quinclorac, which increased it. In some herbicide treatments, reduction in the incorporation into cellulose was accompanied by an increase in the incorporation into other fractions. In order to appreciate the effect of the inhibitors on cell wall partitioning, a cluster and Principal Component Analysis (PCA) based on the relative contribution of [14C]glucose incorporation into the different cell wall fractions were performed, and three groups of compounds were identified. The first group included quinclorac, which increased glucose incorporation into cellulose; the second group consisted of compound 1, CGA 325′615, oxaziclomefone and AE F150944, which decreased the relative glucose incorporation into cellulose but increased it into tightly-bound cellulose fractions; and the third group, comprising flupoxam, triazofenamide and dichlobenil, decreased the relative glucose incorporation into cellulose and increased it into a pectin rich fraction. Full article
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Article
Synthesis and Biological Activities of a 3'-Azido Analogue of Doxorubicin Against Drug-Resistant Cancer Cells
Int. J. Mol. Sci. 2012, 13(3), 3671-3684; https://doi.org/10.3390/ijms13033671 - 19 Mar 2012
Cited by 12 | Viewed by 4396
Abstract
Doxorubicin (DOX), an anthracycline antibiotic, is one of the most active anticancer chemotherapeutic agents. The clinical use of DOX, however, is limited by the dose-dependant P-glycoprotein (P-gp)-mediated resistance. Herein, a 3′-azido analogue of DOX (ADOX) was prepared from daunorubicin (DNR). ADOX exhibited potent [...] Read more.
Doxorubicin (DOX), an anthracycline antibiotic, is one of the most active anticancer chemotherapeutic agents. The clinical use of DOX, however, is limited by the dose-dependant P-glycoprotein (P-gp)-mediated resistance. Herein, a 3′-azido analogue of DOX (ADOX) was prepared from daunorubicin (DNR). ADOX exhibited potent antitumor activities in drug-sensitive (MCF-7 and K562) and drug-resistant cell lines (MCF-7/DNR, K562/DOX), respectively. The drug resistance index (DRI) values of ADOX were much lower than that of DOX. The cytotoxicity experiments of ADOX or DOX against K562/DOX, with or without P-gp inhibitor, indicated that ADOX circumvents resistance by abolishing the P-gp recognition. This conclusion was further supported by drug influx/efflux flow cytometry experiments, as well as by molecular docking of ADOX to P-gp. In vivo animal tests, ADOX exhibited higher activity and less toxicity than DOX. The current data warranted ADOX for additional pre-clinical evaluations for new drug development. Full article
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Article
Synthesis and Antimicrobial Studies of Some Novel Bis-[1,3,4]thiadiazole and Bis-thiazole Pendant to Thieno[2,3-b]thiophene Moiety
Int. J. Mol. Sci. 2012, 13(3), 3661-3670; https://doi.org/10.3390/ijms13033661 - 19 Mar 2012
Cited by 30 | Viewed by 3831
Abstract
The synthetic utility of 3,3’-(3,4-dimethylthieno[2,3-b]thiophene-2,5-diyl)bis (3-oxopropanenitrile) (1) in the synthesis of some novel bis-[1,3,4-thiadiazole] 6a–g and bis-thiazole 10 and 13 derivatives with thieno[2,3-b]thiophene moiety is reported. Antimicrobial evaluation of some selected examples from the synthesized products was carried out and showed [...] Read more.
The synthetic utility of 3,3’-(3,4-dimethylthieno[2,3-b]thiophene-2,5-diyl)bis (3-oxopropanenitrile) (1) in the synthesis of some novel bis-[1,3,4-thiadiazole] 6a–g and bis-thiazole 10 and 13 derivatives with thieno[2,3-b]thiophene moiety is reported. Antimicrobial evaluation of some selected examples from the synthesized products was carried out and showed promising results. Full article
(This article belongs to the Section Biochemistry)
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Article
Prediction of Bioluminescent Proteins Using Auto Covariance Transformation of Evolutional Profiles
Int. J. Mol. Sci. 2012, 13(3), 3650-3660; https://doi.org/10.3390/ijms13033650 - 19 Mar 2012
Cited by 14 | Viewed by 3667
Abstract
Bioluminescent proteins are important for various cellular processes, such as gene expression analysis, drug discovery, bioluminescent imaging, toxicity determination, and DNA sequencing studies. Hence, the correct identification of bioluminescent proteins is of great importance both for helping genome annotation and providing a supplementary [...] Read more.
Bioluminescent proteins are important for various cellular processes, such as gene expression analysis, drug discovery, bioluminescent imaging, toxicity determination, and DNA sequencing studies. Hence, the correct identification of bioluminescent proteins is of great importance both for helping genome annotation and providing a supplementary role to experimental research to obtain insight into bioluminescent proteins’ functions. However, few computational methods are available for identifying bioluminescent proteins. Therefore, in this paper we develop a new method to predict bioluminescent proteins using a model based on position specific scoring matrix and auto covariance. Tested by 10-fold cross-validation and independent test, the accuracy of the proposed model reaches 85.17% for the training dataset and 90.71% for the testing dataset respectively. These results indicate that our predictor is a useful tool to predict bioluminescent proteins. This is the first study in which evolutionary information and local sequence environment information have been successfully integrated for predicting bioluminescent proteins. A web server (BLPre) that implements the proposed predictor is freely available. Full article
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Article
Optimization of Serine Protease Purification from Mango (Mangifera indica cv. Chokanan) Peel in Polyethylene Glycol/Dextran Aqueous Two Phase System
Int. J. Mol. Sci. 2012, 13(3), 3636-3649; https://doi.org/10.3390/ijms13033636 - 19 Mar 2012
Cited by 23 | Viewed by 6358
Abstract
Mango peel is a good source of protease but remains an industrial waste. This study focuses on the optimization of polyethylene glycol (PEG)/dextran-based aqueous two-phase system (ATPS) to purify serine protease from mango peel. The activity of serine protease in different phase systems [...] Read more.
Mango peel is a good source of protease but remains an industrial waste. This study focuses on the optimization of polyethylene glycol (PEG)/dextran-based aqueous two-phase system (ATPS) to purify serine protease from mango peel. The activity of serine protease in different phase systems was studied and then the possible relationship between the purification variables, namely polyethylene glycol molecular weight (PEG, 4000–12,000 g·mol−1), tie line length (−3.42–35.27%), NaCl (−2.5–11.5%) and pH (4.5–10.5) on the enzymatic properties of purified enzyme was investigated. The most significant effect of PEG was on the efficiency of serine protease purification. Also, there was a significant increase in the partition coefficient with the addition of 4.5% of NaCl to the system. This could be due to the high hydrophobicity of serine protease compared to protein contaminates. The optimum conditions to achieve high partition coefficient (84.2) purification factor (14.37) and yield (97.3%) of serine protease were obtained in the presence of 8000 g·mol−1 of PEG, 17.2% of tie line length and 4.5% of NaCl at pH 7.5. The enzymatic properties of purified serine protease using PEG/dextran ATPS showed that the enzyme could be purified at a high purification factor and yield with easy scale-up and fast processing. Full article
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Review
The Intriguing Life of Autophagosomes
Int. J. Mol. Sci. 2012, 13(3), 3618-3635; https://doi.org/10.3390/ijms13033618 - 19 Mar 2012
Cited by 28 | Viewed by 4038
Abstract
Autophagosomes are double-membrane vesicles characteristic of macroautophagy, a degradative pathway for cytoplasmic material and organelles terminating in the lysosomal or vacuole compartment for mammals and yeast, respectively. This highly dynamic, multi-step process requires significant membrane reorganization events at different stages of the macroautophagic [...] Read more.
Autophagosomes are double-membrane vesicles characteristic of macroautophagy, a degradative pathway for cytoplasmic material and organelles terminating in the lysosomal or vacuole compartment for mammals and yeast, respectively. This highly dynamic, multi-step process requires significant membrane reorganization events at different stages of the macroautophagic process. Such events include exchange and flow of lipids and proteins between membranes and vesicles (e.g., during initiation and growth of the phagophore), vesicular positioning and trafficking within the cell (e.g., autophagosome location and movement) and fusion of autophagosomes with the boundary membranes of the degradative compartment. Here, we review current knowledge on the contribution of different organelles to the formation of autophagosomes, their trafficking and fate within the cell. We will consider some of the unresolved questions related to the molecular mechanisms that regulate the “life and death” of the autophagosome. Full article
(This article belongs to the Special Issue Membrane Transport)
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Article
Improvement of Carbon Tetrachloride-Induced Acute Hepatic Failure by Transplantation of Induced Pluripotent Stem Cells without Reprogramming Factor c-Myc
Int. J. Mol. Sci. 2012, 13(3), 3598-3617; https://doi.org/10.3390/ijms13033598 - 16 Mar 2012
Cited by 11 | Viewed by 5170
Abstract
The only curative treatment for hepatic failure is liver transplantation. Unfortunately, this treatment has several major limitations, as for example donor organ shortage. A previous report demonstrated that transplantation of induced pluripotent stem cells without reprogramming factor c-Myc (3-genes iPSCs) attenuates thioacetamide-induced hepatic [...] Read more.
The only curative treatment for hepatic failure is liver transplantation. Unfortunately, this treatment has several major limitations, as for example donor organ shortage. A previous report demonstrated that transplantation of induced pluripotent stem cells without reprogramming factor c-Myc (3-genes iPSCs) attenuates thioacetamide-induced hepatic failure with minimal incidence of tumorigenicity. In this study, we investigated whether 3-genes iPSC transplantation is capable of rescuing carbon tetrachloride (CCl4)-induced fulminant hepatic failure and hepatic encephalopathy in mice. Firstly, we demonstrated that 3-genes iPSCs possess the capacity to differentiate into hepatocyte-like cells (iPSC-Heps) that exhibit biological functions and express various hepatic specific markers. 3-genes iPSCs also exhibited several antioxidant enzymes that prevented CCl4-induced reactive oxygen species production and cell death. Intraperitoneal transplantation of either 3-genes iPSCs or 3-genes iPSC-Heps significantly reduced hepatic necrotic areas, improved hepatic functions, and survival rate in CCl4-treated mice. CCl4-induced hepatic encephalopathy was also improved by 3-genes iPSC transplantation. Hoechst staining confirmed the successful engraftment of both 3-genes iPSCs and 3-genes iPSC-Heps, indicating the homing properties of these cells. The most pronounced hepatoprotective effect of iPSCs appeared to originate from the highest antioxidant activity of 3-gene iPSCs among all transplanted cells. In summary, our findings demonstrated that 3-genes iPSCs serve as an available cell source for the treatment of an experimental model of acute liver diseases. Full article
(This article belongs to the Section Biochemistry)
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Article
Pharmacokinetic Comparison of Ferulic Acid in Normal and Blood Deficiency Rats after Oral Administration of Angelica sinensis, Ligusticum chuanxiong and Their Combination
Int. J. Mol. Sci. 2012, 13(3), 3583-3597; https://doi.org/10.3390/ijms13033583 - 16 Mar 2012
Cited by 66 | Viewed by 5420
Abstract
Radix Angelica Sinensis (RAS) and Rhizome Ligusticum (RLC) combination is a popular herb pair commonly used in clinics for treatment of blood deficiency syndrome in China. The aim of this study is to compare the pharmacokinetic properties of ferulic acid (FA), a main [...] Read more.
Radix Angelica Sinensis (RAS) and Rhizome Ligusticum (RLC) combination is a popular herb pair commonly used in clinics for treatment of blood deficiency syndrome in China. The aim of this study is to compare the pharmacokinetic properties of ferulic acid (FA), a main bioactive constituent in both RAS and RLC, between normal and blood deficiency syndrome animals, and to investigate the influence of compatibility of RAS and RLC on the pharmacokinetic of FA. The blood deficiency rats were induced by injecting 2% Acetyl phenylhydrazine (APH) on the first day, every other day, to a total of five times, at the dosage of 100, 50, 50, 30, 30 mg/kg body mass, respectively. Quantification of FA in rat plasma was achieved by using a simple and rapid HPLC method. Plasma samples were collected at different time points to construct pharmacokinetic profiles by plotting drug concentration versus time, and estimate pharmacokinetic parameters. Between normal and blood deficiency model groups, both AUC(0–t) and Cmax of FA in blood deficiency rats after RAS-RLC extract administration increased significantly (P < 0.05), while clearance (CL) decreased significantly. Among three blood deficiency model groups, t1/2α, Vd, AUC(0–t) and AUC(0–∞) all increased significantly in the RAS-RLC extract group compared with the RAS group. The results indicated that FA was absorbed better and eliminated slower in blood deficiency rats; RLC could significantly prolong the half-life of distribution, increase the volume of distribution and the absorption amount of FA of RAS in blood deficiency rats, which may be due to the synergic action when RAS and RLC were used together to treat blood deficiency syndrome. Full article
(This article belongs to the Section Biochemistry)
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Article
Autophagy in Premature Senescent Cells Is Activated via AMPK Pathway
Int. J. Mol. Sci. 2012, 13(3), 3563-3582; https://doi.org/10.3390/ijms13033563 - 16 Mar 2012
Cited by 30 | Viewed by 3887
Abstract
Autophagy is a highly regulated intracellular process involved in the turnover of most cellular constituents and in the maintenance of cellular homeostasis. In this study, we show that the activity of autophagy increases in H2O2 or RasV12-induced senescent fibroblasts. Inhibiting [...] Read more.
Autophagy is a highly regulated intracellular process involved in the turnover of most cellular constituents and in the maintenance of cellular homeostasis. In this study, we show that the activity of autophagy increases in H2O2 or RasV12-induced senescent fibroblasts. Inhibiting autophagy promotes cell apoptosis in senescent cells, suggesting that autophagy activation plays a cytoprotective role. Furthermore, our data indicate that the increase of autophagy in senescent cells is linked to the activation of transcription factor FoxO3A, which blocks ATP generation by transcriptionally up-regulating the expression of PDK4, an inhibitor of pyruvate dehydrogenase complex, thus leading to AMPK activation and mTOR inhibition. These findings suggest a novel mechanism by which FoxO3A factors can activate autophagy via metabolic alteration. Full article
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Article
A Comparative Study on the Expression, Purification and Functional Characterization of Human Adiponectin in Pichia pastoris and Escherichia coli
Int. J. Mol. Sci. 2012, 13(3), 3549-3562; https://doi.org/10.3390/ijms13033549 - 15 Mar 2012
Cited by 18 | Viewed by 4458
Abstract
Adiponectin is one of the most bioactive substances secreted by adipose tissue and is involved in the protection against metabolic syndrome, artherosclerosis and type II diabetes. Research into the use of adiponectin as a promising drug for metabolic syndromes requires production of this [...] Read more.
Adiponectin is one of the most bioactive substances secreted by adipose tissue and is involved in the protection against metabolic syndrome, artherosclerosis and type II diabetes. Research into the use of adiponectin as a promising drug for metabolic syndromes requires production of this hormone in high quantities considering its molecular isoforms. The objective of this study is to produce recombinant human adiponectin by Pichia pastoris (P-ADP) as a cheap and convenient eukaryotic expression system for potential application in pharmaceutical therapy. For comparison, adiponectin was also expressed using the Escherichia coli (E-ADP) expression system. Adiponectin was constructed by overlap-extension PCR, and cloned in standard cloning vector and hosts. Recombinant expression vectors were cloned in the P. pastoris and E. coli host strains, respectively. SDS-PAGE and western blotting were used to detect and analyse expressed recombinant protein in both systems. Adiponectin was purified by affinity chromatography and quantified using the Bradford Assay. The results of this study indicated that P-ADP quantity (0.111 mg/mL) was higher than that of E-ADP (0.04 mg/mL) and both were produced in soluble form. However, P-ADP was able to form high molecular weights of adiponectin molecules, whilst E-ADP was not able to form isoforms higher than trimer. In addition, P-ADP was more active in lowering blood glucose compared with E-ADP. The two types of proteins were equally efficient and significantly decreased blood triglyceride and increased high density lipoprotein. We conclude that P. pastoris is able to produce high quantity of bioactive adiponectin for potential use in treatment of metabolic syndromes. Full article
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Review
Arsenic and Antimony Transporters in Eukaryotes
Int. J. Mol. Sci. 2012, 13(3), 3527-3548; https://doi.org/10.3390/ijms13033527 - 15 Mar 2012
Cited by 85 | Viewed by 5268
Abstract
Arsenic and antimony are toxic metalloids, naturally present in the environment and all organisms have developed pathways for their detoxification. The most effective metalloid tolerance systems in eukaryotes include downregulation of metalloid uptake, efflux out of the cell, and complexation with phytochelatin or [...] Read more.
Arsenic and antimony are toxic metalloids, naturally present in the environment and all organisms have developed pathways for their detoxification. The most effective metalloid tolerance systems in eukaryotes include downregulation of metalloid uptake, efflux out of the cell, and complexation with phytochelatin or glutathione followed by sequestration into the vacuole. Understanding of arsenic and antimony transport system is of high importance due to the increasing usage of arsenic-based drugs in the treatment of certain types of cancer and diseases caused by protozoan parasites as well as for the development of bio- and phytoremediation strategies for metalloid polluted areas. However, in contrast to prokaryotes, the knowledge about specific transporters of arsenic and antimony and the mechanisms of metalloid transport in eukaryotes has been very limited for a long time. Here, we review the recent advances in understanding of arsenic and antimony transport pathways in eukaryotes, including a dual role of aquaglyceroporins in uptake and efflux of metalloids, elucidation of arsenic transport mechanism by the yeast Acr3 transporter and its role in arsenic hyperaccumulation in ferns, identification of vacuolar transporters of arsenic-phytochelatin complexes in plants and forms of arsenic substrates recognized by mammalian ABC transporters. Full article
(This article belongs to the Special Issue Membrane Transport)
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Article
A High Molar Extinction Coefficient Bisterpyridyl Homoleptic Ru(II) Complex with trans-2-Methyl-2-butenoic Acid Functionality: Potential Dye for Dye-Sensitized Solar Cells
Int. J. Mol. Sci. 2012, 13(3), 3511-3526; https://doi.org/10.3390/ijms13033511 - 14 Mar 2012
Cited by 17 | Viewed by 5001
Abstract
In our continued efforts in the synthesis of ruthenium(II) polypyridine complexes as potential dyes for use in varied applications, such as the dye-sensitized solar cells (DSSCs), this work particularly describes the synthesis, absorption spectrum, redox behavior and luminescence properties of a new homoleptic [...] Read more.
In our continued efforts in the synthesis of ruthenium(II) polypyridine complexes as potential dyes for use in varied applications, such as the dye-sensitized solar cells (DSSCs), this work particularly describes the synthesis, absorption spectrum, redox behavior and luminescence properties of a new homoleptic ruthenium(II) complex bearing a simple trans-2-methyl-2-butenoic acid functionality as the anchoring ligand on terpyridine moiety. The functionalized terpyridine ligand: 4’-(trans-2-methyl-2-butenoic acid)-terpyridyl (L1) was synthesized by aryl bromide substitution on terpyridine in a basic reaction condition under palladium carbide catalysis. In particular, the photophysical and redox properties of the complex formulated as: bis-4’-(trans-2-methyl-2-butenoic acid)-terpyridyl ruthenium(II) bis-hexafluorophosphate [Ru(L1)2(PF6)2] are significantly better compared to those of [Ru(tpy)2]2+ and compare well with those of the best emitters of Ru(II) polypyridine family containing tridentate ligands. Reasons for the improved photophysical and redox properties of the complex may be attributed partly to the presence of a substituted α,β-unsaturated carboxylic acid moiety leading to increase in the length of π-conjugation bond thereby enhancing the MLCT-MC (Metal-to-ligand-charge transfer-metal centred) energy gap, and to the reduced difference between the minima of the excited and ground states potential energy surfaces. Full article
(This article belongs to the Section Materials Science)
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