Micromachines

Research

Jump to: Review

13 pages, 4902 KiB

Open AccessArticle

Green Synthesis of Zinc Oxide (ZnO) Nanoparticles from Green Algae and Their Assessment in Various Biological Applications

by Hajra Hameed, Abdul Waheed, Muhammad Shakeeb Sharif, Muhammad Saleem, Afshan Afreen, Muhammad Tariq, Asif Kamal, Wedad A. Al-onazi, Dunia A. Al Farraj, Shabir Ahmad and Rania M. Mahmoud

Micromachines 2023, 14(5), 928; https://doi.org/10.3390/mi14050928 - 25 Apr 2023

Cited by 29 | Viewed by 5275

Abstract

The biosynthesis of algal-based zinc oxide (ZnO) nanoparticles has shown several advantages over traditional physico-chemical methods, such as lower cost, less toxicity, and greater sustainability. In the current study, bioactive molecules present in Spirogyra hyalina extract were exploited for the biofabrication and capping [...] Read more.

The biosynthesis of algal-based zinc oxide (ZnO) nanoparticles has shown several advantages over traditional physico-chemical methods, such as lower cost, less toxicity, and greater sustainability. In the current study, bioactive molecules present in Spirogyra hyalina extract were exploited for the biofabrication and capping of ZnO NPs, using zinc acetate dihydrate and zinc nitrate hexahydrate as precursors. The newly biosynthesized ZnO NPs were characterized for structural and optical changes through UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX). A color change in the reaction mixture from light yellow to white indicated the successful biofabrication of ZnO NPs. The UV-Vis absorption spectrum peaks at 358 nm (from zinc acetate) and 363 nm (from zinc nitrate) of ZnO NPs confirmed that optical changes were caused by a blue shift near the band edges. The extremely crystalline and hexagonal Wurtzite structure of ZnO NPs was confirmed by XRD. The involvement of bioactive metabolites from algae in the bioreduction and capping of NPs was demonstrated by FTIR investigation. The SEM results revealed spherical-shaped ZnO NPs. In addition to this, the antibacterial and antioxidant activity of the ZnO NPs was investigated. ZnO NPs showed remarkable antibacterial efficacy against both Gram-positive and Gram-negative bacteria. The DPPH test revealed the strong antioxidant activity of ZnO NPs. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Figure 1

18 pages, 2375 KiB

Open AccessArticle

Study of the Embryonic Toxicity of TiO₂ and ZrO₂ Nanoparticles

by Elena Nikolaevna Lyashenko, Leyla Djavadovna Uzbekova, Valeri Vladimirovna Polovinkina, Anastasia Konstantinovna Dorofeeva, Said-Umar Sithalil-ugli Ibragimov, Arslan Ayavovich Tatamov, Albina Gamdullaevna Avkaeva, Anastasia Alekseevna Mikhailova, Inga Shamilevna Tuaeva, Ruslan Kazbekovich Esiev, Sergei Dmitrievich Mezentsev, Marina Alexandrovna Gubanova, Natalya Grigorevna Bondarenko and Alina Yurievna Maslova

Micromachines 2023, 14(2), 363; https://doi.org/10.3390/mi14020363 - 31 Jan 2023

Cited by 15 | Viewed by 2519

Abstract

Currently, the widespread use of TiO₂ and ZrO₂ nanoparticles (NPs) in various industries poses a risk in terms of their potential toxicity. A number of experimental studies provide evidence of the toxic effect of TiO₂ and ZrO₂ NPs on [...] Read more.

Currently, the widespread use of TiO₂ and ZrO₂ nanoparticles (NPs) in various industries poses a risk in terms of their potential toxicity. A number of experimental studies provide evidence of the toxic effect of TiO₂ and ZrO₂ NPs on biological objects. In order to supplement the level of knowledge and assess the risks of toxicity and danger of TiO₂ and ZrO₂ NPs, we decided to conduct a comprehensive experiment to study the embryonic toxicity of TiO₂ and ZrO₂ NPs in pregnant rats. For the experiment, mongrel white rats during pregnancy received aqueous dispersions of powders of TiO₂ and ZrO₂ NPs at a dose of 100 mg/kg/day. To characterize the effect of TiO₂ and ZrO₂ NPs on females and the postnatal ontogenesis of offspring, a complex of physiological and biochemical research methods was used. The results of the experiment showed that TiO₂ NPs as ZrO₂ NPs (100 mg/kg per os) cause few shifts of similar orientation in the maternal body. Neither TiO₂ NPs nor ZrO₂ NPs have an embryonic and teratogenic effect on the offspring in utero, but both modify its postnatal development. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Figure 1

12 pages, 7155 KiB

Open AccessArticle

Synthesis and Characterization of Calcium Silicate Nanoparticles Stabilized with Amino Acids

by Anastasiya A. Blinova, Abdurasul A. Karamirzoev, Asiyat R. Guseynova, David G. Maglakelidze, Tatiana A. Ilyaeva, Batradz A. Gusov, Avetis P. Meliksetyants, Mari M. Pirumian, Maxim A. Taravanov, Maxim A. Pirogov, Dmitriy S. Vakalov, Tatiana V. Bernyukevich, Alexey A. Gvozdenko, Andrey A. Nagdalian and Andrey V. Blinov

Micromachines 2023, 14(2), 245; https://doi.org/10.3390/mi14020245 - 18 Jan 2023

Cited by 3 | Viewed by 2583

Abstract

This work presents the development of a method for the synthesis of calcium silicate nanoparticles stabilized with essential amino acids. CaSiO₃ nanoparticles were obtained through chemical precipitation. In the first stage, the optimal calcium-containing precursor was determined. The samples were examined using [...] Read more.

This work presents the development of a method for the synthesis of calcium silicate nanoparticles stabilized with essential amino acids. CaSiO₃ nanoparticles were obtained through chemical precipitation. In the first stage, the optimal calcium-containing precursor was determined. The samples were examined using scanning electron microscopy. It was found that Ca(CH₃COO)₂ was the optimal calcium-containing precursor. Then, the phase composition of calcium silicate was studied using X-ray phase analysis. The results showed the presence of high-intensity bands in the diffractogram, which characterized the phase of the nanosized CaSiO₃—wollastonite. In the next stage, the influence of the type of amino acid on the microstructure of calcium silicate was studied. The amnio acids studied were valine, L-leucine, L-isoleucine, L-methionine, L-threonine, L-lysine, L-phenylalanine, and L-tryptophan. The analysis of the SEM micrographs showed that the addition of amino acids did not significantly affect the morphology of the CaSiO₃ samples. The surface of the CaSiO₃ samples, both without a stabilizer and with amino acids, was represented by irregularly shaped aggregates consisting of nanoparticles with a diameter of 50–400 nm. Further, in order to determine the optimal amino acid to use to stabilize nanoparticles, computerized quantum chemical modeling was carried out. Analysis of the data obtained showed that the most energetically favorable interaction was the CaSiO₃–L-methionine configuration, where the interaction occurs through the amino group of the amino acid; the energy value of which was −2058.497 kcal/mol. To confirm the simulation results, the samples were examined using IR spectroscopy. An analysis of the results showed that the interaction of calcium silicate with L-methionine occurs via the formation of a bond through the NH₃⁺ group of the amino acid. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Figure 1

18 pages, 13457 KiB

Open AccessArticle

Synergistic Anticandidal Activities of Greenly Synthesized ZnO Nanomaterials with Commercial Antifungal Agents against Candidal Infections

by Mohamed Taha Yassin, Abdallah M. Elgorban, Abdulaziz A. Al-Askar, Essam Nageh Sholkamy, Fuad Ameen and Khalid Maniah

Micromachines 2023, 14(1), 209; https://doi.org/10.3390/mi14010209 - 14 Jan 2023

Cited by 16 | Viewed by 2250

Abstract

The high occurrence of mycological resistance to conventional antifungal agents results in significant illness and death rates among immunodeficient patients. In addition, the underprivileged therapeutic results of conventional antifungal agents, besides the potential toxicity resulting from long term therapy necessitate the fabrication of [...] Read more.

The high occurrence of mycological resistance to conventional antifungal agents results in significant illness and death rates among immunodeficient patients. In addition, the underprivileged therapeutic results of conventional antifungal agents, besides the potential toxicity resulting from long term therapy necessitate the fabrication of efficient antimicrobial combinations. Hence, the objective of the present investigation is to synthesize, characterize and investigate the anticandidal action of green zinc oxide nanoparticles (ZnO-NPs) formulated using Camellia sinensis leaf extract against three candidal pathogens. The eco-friendly synthesized ZnO-NPs were characterized utilizing different physicochemical methods and their anticandidal potency was tested utilizing a disk diffusion assay. In this setting, the size of the biofabricated ZnO-NPs was detected using transmission electron microscope (TEM) micrographs, recording an average particle size of 19.380 ± 2.14 nm. In addition, zeta potential analysis revealed that the ZnO-NPs surface charge was −4.72 mV. The biogenic ZnO-NPs reveal the highest anticandidal activity against the C. tropicalis strain, demonstrating relative suppressive zones measured at 35.16 ± 0.13 and 37.87 ± 0.24 mm in diameter for ZnO-NPs concentrations of 50 and 100 μg/disk, respectively. Excitingly, Candida glabrata showed a high susceptibility to the biofabricated ZnO nanomaterials at both ZnO-NPs’ concentrations (50 and 100 μg/disk) compared to the control. Moreover, the biosynthesized ZnO-NPs revealed potential synergistic effectiveness with nystatin and terbinafine antifungal agents against the concerned strains. The maximum synergistic efficiency was noticed against the C. glabrata strain, demonstrating relative synergistic percentages of 23.02 and 45.9%, respectively. The biogenic ZnO-NPs revealed no hemolytic activity against human erythrocytes revealing their biosafety and hemocompatibility. Finally, the high anticandidal effectiveness of biogenic ZnO-NPs against the concerned candidal pathogens, as well as potential synergistic patterns with conventional antifungal agents such as nystatin and terbinafine, emphasize the prospective application of these combinations for the fabrication of biocompatible and highly efficient antifungal agents. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Figure 1

15 pages, 4307 KiB

Open AccessArticle

Evaluation of Antifungal Properties of Titania P25

by Kunlei Wang, Oliwia Paszkiewicz, Mewin Vincent, Patrycja Henkiel, Damian Kowalski, Ewa Kowalska and Agata Markowska-Szczupak

Micromachines 2022, 13(11), 1851; https://doi.org/10.3390/mi13111851 - 28 Oct 2022

Viewed by 1802

Abstract

Commercial titania photocatalyst—P25 was chosen for an antifungal property examination due to it exhibiting one of the highest photocatalytic activities among titania photocatalysts. Titania P25 was homogenized first (HomoP25) and then annealed at different temperatures. Additionally, HomoP25 was modified with 0.5 wt% or [...] Read more.

Commercial titania photocatalyst—P25 was chosen for an antifungal property examination due to it exhibiting one of the highest photocatalytic activities among titania photocatalysts. Titania P25 was homogenized first (HomoP25) and then annealed at different temperatures. Additionally, HomoP25 was modified with 0.5 wt% or 2.0 wt% of platinum by a photodeposition method. The obtained samples were characterized by diffuse-reflectance spectroscopy (DRS), X-ray photoabsorption spectroscopy (XPS), X-ray diffraction (XRD) and Raman spectroscopy. Moreover, photocatalytic activity was tested for methanol dehydrogenation under UV/vis irradiation. The spore-destroying effect of photocatalysts was investigated against two mold fungal species, i.e., Aspergillus fumigatus and Aspergillus niger. Both the mycelium growth and API ZYM (estimation of enzymatic activity) tests were applied for the assessment of antifungal effect. It was found that annealing caused a change of surface properties of the titania samples, i.e., an increase in the noncrystalline part, a growth of particles and enhanced oxygen adsorption on its surface, which resulted in an increase in both the hydrogen evolution rate and the antifungal effect. Titania samples annealed at 300–500 °C were highly active during 60-min UV/vis irradiation, inhibiting the germination of both fungal spores, whereas titania modification with platinum (0.5 and 2.0 wt%) had negligible effect, despite being highly active for hydrogen evolution. The control experiments revealed the lack of titania activity in the dark, as well as high resistance of fungi for applied UV/vis irradiation in the absence of photocatalysts. Moreover, the complete inhibition of 19 hydrolases, secreted by both tested fungi, was noted under UV/vis irradiation on the annealed P25 sample. It is proposed that titania photocatalysts of large particle sizes (>150 nm) and enriched surface with oxygen might efficiently destroy fungal structures under mild irradiation conditions and, thus, be highly promising as covering materials for daily products. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Graphical abstract

15 pages, 7608 KiB

Open AccessArticle

Computational Study of Magnetic Particle Motion inside the Nasal Cavity under the Impact of an External Magnetic Field for Biomedical Applications

by Nikolaos Pradakis, Nikolaos Maniotis and Theodoros Samaras

Micromachines 2022, 13(11), 1816; https://doi.org/10.3390/mi13111816 - 24 Oct 2022

Viewed by 1498

Abstract

The blood–brain barrier is a highly selective semipermeable border that separates blood circulation from the brain and hinders the accumulation of substances in the central nervous system. Hence, a treatment plan aiming to combat neurodegenerative diseases may be restricted. The exploitation of the [...] Read more.

The blood–brain barrier is a highly selective semipermeable border that separates blood circulation from the brain and hinders the accumulation of substances in the central nervous system. Hence, a treatment plan aiming to combat neurodegenerative diseases may be restricted. The exploitation of the nose–brain pathway could be a promising bypass method. However, pharmaceutical uptake through the olfactory epithelium is insignificant in terms of treatment, if relying only on fluid dynamic interactions. The main reasons for this are the highly complicated geometry of the nose and the residence time of the substance. The issue can be tackled by using magnetic particles as drug carriers. With the application of an external magnetic field, further control of the particle motion can be achieved, leading to increased uptake. The present work studies this approach computationally by employing magnetite particles with a radius of

7.5 μ m

while a magnetic field is applied with a permanent neodymium-iron-boron magnet of

9.5 \times 10^{5}

A/m magnetization. Through this investigation, the best drug delivery protocol achieved a 2% delivery efficiency. The most significant advantage of this protocol is its straightforward design, which does not require complex equipment, thus rendering the protocol portable and manageable for frequent dosing or at-home administration. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Figure 1

16 pages, 2012 KiB

Open AccessArticle

Synthesised Conductive/Magnetic Composite Particles for Magnetic Ablations of Tumours

by Chiang-Wen Lee, Ju-Fang Liu, Wen-Chun Wei, Ming-Hsien Chiang, Ting-Yuan Chen, Shu-Hsien Liao, Yao-Chang Chiang, Wen-Cheng Kuo, Kuen-Lin Chen, Kuo-Ti Peng, Yen-Bin Liu and Jen-Jie Chieh

Micromachines 2022, 13(10), 1605; https://doi.org/10.3390/mi13101605 - 27 Sep 2022

Viewed by 1802

Abstract

Ablation is a clinical cancer treatment, but some demands are still unsatisfied, such as electromagnetic interferences amongst multiple ablation needles during large tumour treatments. This work proposes a physical synthesis for composite particles of biocompatible iron oxide particles and liquid metal gallium (Ga) [...] Read more.

Ablation is a clinical cancer treatment, but some demands are still unsatisfied, such as electromagnetic interferences amongst multiple ablation needles during large tumour treatments. This work proposes a physical synthesis for composite particles of biocompatible iron oxide particles and liquid metal gallium (Ga) with different alternative-current (AC)-magnetic-field-induced heat mechanisms of magnetic particle hyperthermia and superior resistance heat. By some imaging, X-ray diffraction, and vibrating sample magnetometer, utilised composite particles were clearly identified as the cluster of few iron oxides using the small weight ratio of high-viscosity liquid metal Ga as conjugation materials without surfactants for physical targeting of limited fluidity. Hence, well penetration inside the tissue and the promotion rate of heat generation to fit the ablation requirement of at least 60 °C in a few seconds are achieved. For the injection and the post-injection magnetic ablations, the volume variation ratios of mice dorsal tumours on Day 12 were expressed at around one without tumour growth. Its future powerful potentiality is expected through a percutaneous injection. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Figure 1

17 pages, 7470 KiB

Open AccessArticle

Biological and Physico-Chemical Properties of Composite Layers Based on Magnesium-Doped Hydroxyapatite in Chitosan Matrix

by Simona Liliana Iconaru, Carmen Steluta Ciobanu, Gabriel Predoi, Krzysztof Rokosz, Mariana Carmen Chifiriuc, Coralia Bleotu, George Stanciu, Radu Hristu, Steinar Raaen, Stefania Mariana Raita, Liliana Ghegoiu, Monica Luminita Badea and Daniela Predoi

Micromachines 2022, 13(10), 1574; https://doi.org/10.3390/mi13101574 - 22 Sep 2022

Cited by 10 | Viewed by 1828

Abstract

In the present study, we report the development and characterization of composite layers (by spin coating) based on magnesium-doped hydroxyapatite in a chitosan matrix, (Ca_10−xMg_x(PO₄)₆(OH)₂; x_Mg = 0, 0.08 and 0.3; HApCh, [...] Read more.

In the present study, we report the development and characterization of composite layers (by spin coating) based on magnesium-doped hydroxyapatite in a chitosan matrix, (Ca_10−xMg_x(PO₄)₆(OH)₂; x_Mg = 0, 0.08 and 0.3; HApCh, 8MgHApCh and 30MgHApCh). The MgHApCh composite layers were investigated using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray photoelectron spectroscopy (XPS) techniques. The in vitro biological evaluation included the assessment of their cytotoxicity on MG63 osteoblast-like cells and antifungal activity against Candida albicans ATCC 10231 fungal cell lines. The results of the physico-chemical characterization highlighted the obtaining of uniform and homogeneous composite layers. In addition, the biological assays demonstrated that the increase in the magnesium concentration in the samples enhanced the antifungal effect but also decreased their cytocompatibility. However, for certain optimal magnesium ion concentrations, the composite layers presented both excellent biocompatibility and antifungal properties, suggesting their promising potential for biomedical applications in both implantology and dentistry. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Figure 1

12 pages, 2724 KiB

Open AccessArticle

Biocontrol of Fruit Rot of Litchi chinensis Using Zinc Oxide Nanoparticles Synthesized in Azadirachta indica

by Junaid Ahmed, Musrat Ali, Huda M. Sheikh, Manal O. Al-Kattan, Farhana, Urooj Haroon, Masoumeh Safaeishakib, Mahnoor Akbar, Asif Kamal, Mohammad Sameer Zubair and Muhammad Farooq Hussain Munis

Micromachines 2022, 13(9), 1461; https://doi.org/10.3390/mi13091461 - 3 Sep 2022

Cited by 10 | Viewed by 2537

Abstract

Lychee (Litchi chinensis Sonn.) is a famous fruit species of tropical and subtropical regions of the world and many biotic and abiotic stresses affect its yield. In this study, lychee fruit rot has been observed and its incidence has been controlled by [...] Read more.

Lychee (Litchi chinensis Sonn.) is a famous fruit species of tropical and subtropical regions of the world and many biotic and abiotic stresses affect its yield. In this study, lychee fruit rot has been observed and its incidence has been controlled by using zinc oxide nanoparticles (ZnO NPs). Diseased lychee fruits were collected and diagnosed to identify disease-causing pathogens. Morphological appearance, microscopic observation, and sequence analysis of the amplified ITS region identified this isolated pathogen as Aspergillus niger. To control this problem, ZnO NPs were prepared in the leaf extract of Azadirachta indica. Before their antifungal activity, ZnO NPs were characterized using sophisticated approaches. FTIR revealed the presence of reducing and stabilizing molecules on ZnO NPs including alcohol, carboxylic acid, alkyl halide, amine, and alkyl halide. Crystalline nature and average size (29.024 nm) of synthesized ZnO NPs were described by X-ray diffraction. EDX analysis depicted the mass percentage of zinc (30.15%) and oxygen (14.90%). SEM analysis displayed the irregular shape of nanoparticles and confirmed the nano-size of ZnO NPs. Maximum mycelial growth inhibition (70.5%) was observed at 1.0 mg/mL concentration of ZnO NPs in vitro. In in-vivo disease-control analysis, maximum control of lychee fruit rot disease was observed at the same concentration. These results reveal the potential use of these ZnO NPs on a larger scale to replace hazardous chemical fungicides. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Figure 1

11 pages, 1622 KiB

Open AccessArticle

Biosynthesis of Silver Nanoparticles Using Azadirachta indica and Their Antioxidant and Anticancer Effects in Cell Lines

by S. Anitha Kumari, Anita K. Patlolla and P. Madhusudhanachary

Micromachines 2022, 13(9), 1416; https://doi.org/10.3390/mi13091416 - 28 Aug 2022

Cited by 14 | Viewed by 2024

Abstract

In the present study, silver nanoparticles (Ag-NPs) were synthesized using Azadirachta indica extract and evaluated for their in vitro antioxidant activity and cytotoxicity efficacy against MCF-7 and HeLa cells. The silver nanoparticles (Ag-NPs) were formed within 40 min and after preliminary confirmation by [...] Read more.

In the present study, silver nanoparticles (Ag-NPs) were synthesized using Azadirachta indica extract and evaluated for their in vitro antioxidant activity and cytotoxicity efficacy against MCF-7 and HeLa cells. The silver nanoparticles (Ag-NPs) were formed within 40 min and after preliminary confirmation by UV-visible spectroscopy (peak observed at 375 nm), they were characterized using a transmission electron microscope (TEM) and dynamic light scattering (DLS). The TEM images showed the spherical shape of the biosynthesized Ag-NPs with particle sizes in the range of 10 to 60 nm, and compositional analysis was carried out. The cytotoxicity and antioxidant activity of various concentrations of biosynthesized silver nanoparticles, Azadirachta indica extract, and a standard ranging from 0.2 to 1.0 mg/mL were evaluated. The 2,2-Diphenyl-1-picrylhydrazyl (DPPH) activity of the biosynthesized Ag-NPs and aqueous leaf extract increased in a dose-dependent manner, with average IC₅₀ values of the biosynthesized Ag-NPs, aqueous leaf extract, and ascorbic acid (standard) of 0.70 ± 0.07, 1.63 ± 0.09, and 0.25 ± 0.09 mg/mL, respectively. Furthermore, higher cytotoxicity was exhibited in both the MCF-7 and HeLa cell lines in a dose-dependent manner. The average IC₅₀ values of the biosynthesized Ag-NPs, aqueous leaf extract, and cisplatin (standard) were 0.90 ± 0.07, 1.85 ± 0.01, and 0.56 ± 0.08 mg/mL, respectively, with MCF-7 cell lines and 0.85 ± 0.01, 1.76 ± 0.08, 0.45 ± 0.10 mg/mL, respectively, with HeLa cell lines. Hence, this study resulted in an efficient green reductant for producing silver nanoparticles that possess cytotoxicity and antioxidant activity against MCF-7 and HeLa cells. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Figure 1

12 pages, 9027 KiB

Open AccessArticle

Highly Durable Antimicrobial Tantalum Nitride/Copper Coatings on Stainless Steel Deposited by Pulsed Magnetron Sputtering

by Thangavel Elangovan, Athinarayanan Balasankar, Selvaraj Arokiyaraj, Ramaseshan Rajagopalan, Rani P. George, Tae Hwan Oh, Parasuraman Kuppusami and Subramaniyan Ramasundaram

Micromachines 2022, 13(9), 1411; https://doi.org/10.3390/mi13091411 - 27 Aug 2022

Cited by 4 | Viewed by 1882

Abstract

Highly durable and antimicrobial tantalum nitride/copper (TaN/Cu) nanocomposite coatings were deposited on D-9 stainless steel substrates by pulsed magnetron sputtering. The Cu content in the coating was varied in the range of 1.42–35.42 atomic % (at.%). The coatings were characterized by electron probe [...] Read more.

Highly durable and antimicrobial tantalum nitride/copper (TaN/Cu) nanocomposite coatings were deposited on D-9 stainless steel substrates by pulsed magnetron sputtering. The Cu content in the coating was varied in the range of 1.42–35.42 atomic % (at.%). The coatings were characterized by electron probe microanalyzer, X-ray diffraction, scanning electron microscope and atomic force microscope. The antibacterial properties of the TaN/Cu coatings against gram-negative Pseudomonas aeruginosa were evaluated using a cell culture test. The peak hardness and Young’s modulus of TaN/Cu with 10.46 at.% Cu were 24 and 295 GPa, respectively, which amounted to 15 and 41.67% higher than Cu-free TaN. Among all, TaN/Cu with 10.46 at.% exhibited the lowest friction coefficient. The TaN/Cu coatings exhibited significantly higher antibacterial activity than Cu-free TaN against Pseudomonas aeruginosa. On TaN, the bacterial count was about 4 × 10⁶ CFU, whereas it was dropped to 1.2 × 10² CFU in case of TaN/Cu with 10.46 at.% Cu. The bacterial count was decreased from 9 to 6 when the Cu content increased from 25.54 to 30.04 at.%. Live bacterial cells were observed in the SEM images of TaN, and dead cells were found on TaN/Cu. Overall, TaN/Cu with 10.46 at.% Cu was found to be a potential coating composition in terms of higher antimicrobial activity and mechanical durability. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Figure 1

15 pages, 4974 KiB

Open AccessArticle

Green Production of Functionalized Few-Layer Graphene–Silver Nanocomposites Using Gallnut Extract for Antibacterial Application

by Yingjie Bu, Anamika Kushwaha, Lalit Goswami and Beom-Soo Kim

Micromachines 2022, 13(8), 1232; https://doi.org/10.3390/mi13081232 - 31 Jul 2022

Cited by 12 | Viewed by 1778

Abstract

Recently, there has been much attention paid to functionalized few-layer graphene (FFG) owing to its many biomedical applications, such as in bioimaging, biosensors, drug delivery, tissue scaffolds, nanocarriers, etc. Hence, the preparation of FFG has now become of great interest to researchers. The [...] Read more.

Recently, there has been much attention paid to functionalized few-layer graphene (FFG) owing to its many biomedical applications, such as in bioimaging, biosensors, drug delivery, tissue scaffolds, nanocarriers, etc. Hence, the preparation of FFG has now become of great interest to researchers. The present study systematically investigates the utilization of gallnut extract (GNE) during the process of high-shear exfoliation for the efficient conversion of expanded graphite to FFG. Various parameters, such as GNE concentration, graphite concentration, exfoliation time, and the rotation speed of the high-shear mixer, were initially optimized for FFG production. The prepared FFG was characterized in terms of surface functionality and morphology using Raman spectra, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy, and scanning electron microscopy analyses. Further, the conjugation of FFG with Ag was confirmed by XRD, XPS, and energy-dispersive X-ray spectra. The Ag–FFG composite exhibited antibacterial activity against both Gram-positive and Gram-negative bacteria through the agar well diffusion method. This study provides an efficient, economical, and eco-friendly FFG and Ag–FFG production method for biomedical applications. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Figure 1

16 pages, 3409 KiB

Open AccessArticle

Mechanical Force Acting on Ferrogel in a Non-Uniform Magnetic Field: Measurements and Modeling

by Felix A. Blyakhman, Alexander P. Safronov, Andrey Yu. Zubarev, Grigory Yu. Melnikov, Sergey Yu. Sokolov, Aitor Larrañaga Varga and Galina V. Kurlyandskaya

Micromachines 2022, 13(8), 1165; https://doi.org/10.3390/mi13081165 - 23 Jul 2022

Cited by 4 | Viewed by 1601

Abstract

The development of magnetoactive microsystems for targeted drug delivery, magnetic biodetection, and replacement therapy is an important task of present day biomedical research. In this work, we experimentally studied the mechanical force acting in cylindrical ferrogel samples due to the application of a [...] Read more.

The development of magnetoactive microsystems for targeted drug delivery, magnetic biodetection, and replacement therapy is an important task of present day biomedical research. In this work, we experimentally studied the mechanical force acting in cylindrical ferrogel samples due to the application of a non-uniform magnetic field. A commercial microsystem is not available for this type of experimental study. Therefore, the original experimental setup for measuring the mechanical force on ferrogel in a non-uniform magnetic field was designed, calibrated, and tested. An external magnetic field was provided by an electromagnet. The maximum intensity at the surface of the electromagnet was 39.8 kA/m and it linearly decreased within 10 mm distance from the magnet. The Ferrogel samples were based on a double networking polymeric structure which included a chemical network of polyacrylamide and a physical network of natural polysaccharide guar. Magnetite particles, 0.25 micron in diameter, were embedded in the hydrogel structure, up to 24% by weight. The forces of attraction between an electromagnet and cylindrical ferrogel samples, 9 mm in height and 13 mm in diameter, increased with field intensity and the concentration of magnetic particles, and varied within 0.1–30 mN. The model provided a fair evaluation of the mechanical forces that emerged in ferrogel samples placed in a non-uniform magnetic field and proved to be useful for predicting the deformation of ferrogels in practical bioengineering applications. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Figure 1

9 pages, 3304 KiB

Open AccessFeature PaperEditor’s ChoiceCommunication

Enzymatic and Cellular Degradation of Carbon-Based Biconcave Nanodisks

by Zhiyong Wei, Qingxin Mu, Hui Wang, Guanyou Lin and Miqin Zhang

Micromachines 2022, 13(7), 1144; https://doi.org/10.3390/mi13071144 - 19 Jul 2022

Cited by 1 | Viewed by 1665

Abstract

The assessment of the biodegradability of nanomaterials is of pragmatic importance for understanding the interactions between nanomaterials and biological systems and for the determination of ultimate fate of these materials as well as their potential use. We recently developed carbon-based biconcave nanodisks (CBBNs) [...] Read more.

The assessment of the biodegradability of nanomaterials is of pragmatic importance for understanding the interactions between nanomaterials and biological systems and for the determination of ultimate fate of these materials as well as their potential use. We recently developed carbon-based biconcave nanodisks (CBBNs) serving as a versatile nanocarrier for enhanced accumulation in tumors and combined photothermal-chemotherapy. Here, we investigate both the enzymatic and cellular degradation of CBBNs by monitoring their cellular response with electron microscopy, near-infrared absorbance spectroscopy, and cell viability and oxidative stress assessments. Our results show that CBBNs underwent significant degradation in solutions catalyzed by horseradish peroxidase (HRP) and hydrogen peroxide (H₂O₂), or in the presence of macrophage cells. The ability of CBBNs to be degraded in biological systems provides suitability for their future biomedical applications. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Graphical abstract

23 pages, 15734 KiB

Open AccessArticle

Surface-Oxidized Polymer-Stabilized Silver Nanoparticles as a Covering Component of Suture Materials

by Andrey Vladimirovich Blinov, Andrey Ashotovich Nagdalian, Sergey Nikolaevich Povetkin, Alexey Alekseevich Gvozdenko, Marina Nikolaevna Verevkina, Igor Vladimirovich Rzhepakovsky, Mariya Sergeevna Lopteva, David Guramievich Maglakelidze, Tatyana Semenovna Kataeva, Anastasiya Aleksandrovna Blinova, Alexey Borisovich Golik, Galina Vladimirovna Osipchuk and Mohammad Ali Shariati

Micromachines 2022, 13(7), 1105; https://doi.org/10.3390/mi13071105 - 14 Jul 2022

Cited by 39 | Viewed by 2529

Abstract

In this work, we obtained silver nanoparticles stabilized with polyvinylpyrrolidone, ranging in size from 70 to 110 nm, which exhibits good crystallinity and anisotropic structure. For the first time, we studied the influence of the molar ratio of silver between silver and peroxide [...] Read more.

In this work, we obtained silver nanoparticles stabilized with polyvinylpyrrolidone, ranging in size from 70 to 110 nm, which exhibits good crystallinity and anisotropic structure. For the first time, we studied the influence of the molar ratio of silver between silver and peroxide on the oxidation process of the nanoparticles and determined the regularities of this process by analyzing changes in absorption spectra. Our results showed that at molar ratios of Ag:H₂O₂ = 1:1 and 1:5, dependences of changes in the intensity, position and half-width of the absorption band of the plasmon resonance are rectilinear. In vivo studies of silver nanoparticles have shown that silver nanoparticles belong to the toxicity class III (moderately hazardous substance) and to the third group according to the degree of accumulation. We established that silver nanoparticles and oxidized silver nanoparticles form a uniform layer on the surface of the suture material. We found that the use of the suture material with silver nanoparticles and oxidized silver nanoparticles does not cause allergic reactions in the organisms of laboratory animals. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Figure 1

14 pages, 3471 KiB

Open AccessArticle

Influence of Polyvinylpyrrolidone Concentration on Properties and Anti-Bacterial Activity of Green Synthesized Silver Nanoparticles

by Raghad Zein, Ibrahim Alghoraibi, Chadi Soukkarieh, Mohammad Taher Ismail and Abdalrahim Alahmad

Micromachines 2022, 13(5), 777; https://doi.org/10.3390/mi13050777 - 15 May 2022

Cited by 26 | Viewed by 4076

Abstract

Environmentally green synthesis of stable polyvinyl pyrrolidone (PVP)-capped silver nanoparticles (PVP-AgNPs) was successfully carried out. The present study focused on investigating the influence of adding PVP during the synthesis process on the size, optical properties and antibacterial effect of silver nanoparticles produced. An [...] Read more.

Environmentally green synthesis of stable polyvinyl pyrrolidone (PVP)-capped silver nanoparticles (PVP-AgNPs) was successfully carried out. The present study focused on investigating the influence of adding PVP during the synthesis process on the size, optical properties and antibacterial effect of silver nanoparticles produced. An aqueous extract of Eucalyptus camaldulensis leaves was used as a reducing agent. The effects of different PVP concentrations and reducing time on the synthesis of nanoparticles (NPs) were characterized by UV–Vis spectrophotometry, scanning electron microscopy (SEM), energy dispersive spectrum (EDX), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS) and nano tracker analysis (NTA). The addition of PVP was studied. The prepared PVP-AgNPs were spherical with an average size of 13 nm. FTIR analysis confirmed that PVP protects AgNPs by a coordination bond between silver nanoparticles and both N and O of PVP. DLS results indicated the good dispersion of silver nanoparticles. PVP-AgNPs were found to be stable for nearly 5 months. Antibacterial studies through the agar well diffusion method confirmed that silver nanoparticles synthesized using PVP had no inhibitor activity toward Gram-positive and Gram-negative bacteria as opposed to silver nanoparticles prepared without adding PVP, which showed a significant antibacterial activity towards some of the tested pathogens. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Figure 1

Review

Jump to: Research

43 pages, 8851 KiB

Open AccessReview

Nanoantioxidant Materials: Nanoengineering Inspired by Nature

by Fotini Fragou, Annita Theofanous, Yiannis Deligiannakis and Maria Louloudi

Micromachines 2023, 14(2), 383; https://doi.org/10.3390/mi14020383 - 4 Feb 2023

Cited by 4 | Viewed by 2655

Abstract

Oxidants are very active compounds that can cause damage to biological systems under specific environmental conditions. One effective way to counterbalance these adverse effects is the use of anti-oxidants. At low concentrations, an antioxidant is defined as a compound that can delay, control, [...] Read more.

Oxidants are very active compounds that can cause damage to biological systems under specific environmental conditions. One effective way to counterbalance these adverse effects is the use of anti-oxidants. At low concentrations, an antioxidant is defined as a compound that can delay, control, or prevent an oxidative process. Antioxidants exist in plants, soil, and minerals; therefore, nature is a rich source of natural antioxidants, such as tocopherols and polyphenols. In nature, antioxidants perform in tandem with their bio-environment, which may tune their activity and protect them from degradation. In vitro use of antioxidants, i.e., out of their biomatrix, may encounter several drawbacks, such as auto-oxidation and polymerization. Artificial nanoantioxidants can be developed via surface modification of a nanoparticle with an antioxidant that can be either natural or synthetic, directly mimicking a natural antioxidant system. In this direction, state-of-the-art nanotechnology has been extensively incorporated to overcome inherent drawbacks encountered in vitro use of antioxidants, i.e., out of their biomatrix, and facilitate the production and use of antioxidants on a larger scale. Biomimetic nanoengineering has been adopted to optimize bio-medical antioxidant systems to improve stability, control release, enhance targeted administration, and overcome toxicity and biocompatibility issues. Focusing on biotechnological sciences, this review highlights the importance of nanoengineering in developing effective antioxidant structures and comparing the effectiveness of different nanoengineering methods. Additionally, this study gathers and clarifies the different antioxidant mechanisms reported in the literature and provides a clear picture of the existing evaluation methods, which can provide vital insights into bio-medical applications. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Graphical abstract

21 pages, 3895 KiB

Open AccessReview

Recent Trends and Opportunities for the Targeted Immuno-Nanomaterials for Cancer Theranostics Applications

by Clyde John, Kaahini Jain, Hema Brindha Masanam, Ashwin Kumar Narasimhan and Arutselvan Natarajan

Micromachines 2022, 13(12), 2217; https://doi.org/10.3390/mi13122217 - 14 Dec 2022

Cited by 1 | Viewed by 2713

Abstract

The targeted delivery of cancer immunotherapies has increased noticeably in recent years. Recent advancements in immunotherapy, particularly in blocking the immune checkpoints (ICs) axis, have shown favorable treatment outcomes for multiple types of cancer including melanoma and non-small-cell lung cancer (NSLC). Engineered micromachines, [...] Read more.

The targeted delivery of cancer immunotherapies has increased noticeably in recent years. Recent advancements in immunotherapy, particularly in blocking the immune checkpoints (ICs) axis, have shown favorable treatment outcomes for multiple types of cancer including melanoma and non-small-cell lung cancer (NSLC). Engineered micromachines, including microparticles, and nanoplatforms (organic and inorganic), functionalized with immune agonists can effectively deliver immune-targeting molecules to solid tumors. This review focuses on the nanomaterial-based strategies that have shown promise in identifying and targeting various immunological markers in the tumor microenvironment (TME) for cancer diagnosis and therapy. Nanomaterials-based cancer immunotherapy has improved treatment outcomes by triggering an immune response in the TME. Evaluating the expression levels of ICs in the TME also could potentially aid in diagnosing patients who would respond to IC blockade therapy. Detecting immunological checkpoints in the TME using noninvasive imaging systems via tailored nanosensors improves the identification of patient outcomes in immuno-oncology (IO). To enhance patient-specific analysis, lab-on-chip (LOC) technology is a rapid, cost-effective, and accurate way of recapitulating the TME. Such novel nanomaterial-based technologies have been of great interest for testing immunotherapies and assessing biomarkers. Finally, we provide a perspective on the developments in artificial intelligence tools to facilitate ICs-based nano theranostics toward cancer immunotherapy. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Figure 1

15 pages, 1106 KiB

Open AccessReview

Hemolytic Activity of Nanoparticles as a Marker of Their Hemocompatibility

by Saul Yedgar, Gregory Barshtein and Alexander Gural

Micromachines 2022, 13(12), 2091; https://doi.org/10.3390/mi13122091 - 27 Nov 2022

Cited by 21 | Viewed by 3801

Abstract

The potential use of nanomaterials in medicine offers opportunities for novel therapeutic approaches to treating complex disorders. For that reason, a new branch of science, named nanotoxicology, which aims to study the dangerous effects of nanomaterials on human health and on the environment, [...] Read more.

The potential use of nanomaterials in medicine offers opportunities for novel therapeutic approaches to treating complex disorders. For that reason, a new branch of science, named nanotoxicology, which aims to study the dangerous effects of nanomaterials on human health and on the environment, has recently emerged. However, the toxicity and risk associated with nanomaterials are unclear or not completely understood. The development of an adequate experimental strategy for assessing the toxicity of nanomaterials may include a rapid/express method that will reliably, quickly, and cheaply make an initial assessment. One possibility is the characterization of the hemocompatibility of nanomaterials, which includes their hemolytic activity as a marker. In this review, we consider various factors affecting the hemolytic activity of nanomaterials and draw the reader’s attention to the fact that the formation of a protein corona around a nanoparticle can significantly change its interaction with the red cell. This leads us to suggest that the nanomaterial hemolytic activity in the buffer does not reflect the situation in the blood plasma. As a recommendation, we propose studying the hemocompatibility of nanomaterials under more physiologically relevant conditions, in the presence of plasma proteins in the medium and under mechanical stress. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Figure 1

18 pages, 1661 KiB

Open AccessReview

Drug Delivery Systems and Flavonoids: Current Knowledge in Melanoma Treatment and Future Perspectives

by Catarina Cunha, Ana L. Daniel-da-Silva and Helena Oliveira

Micromachines 2022, 13(11), 1838; https://doi.org/10.3390/mi13111838 - 27 Oct 2022

Cited by 9 | Viewed by 1959

Abstract

Melanoma is an aggressive form of skin cancer with a high prevalence in the population. An early diagnosis is crucial to cure this disease. Still, when this is not possible, combining potent pharmacological agents and effective drug delivery systems is essential to achieve [...] Read more.

Melanoma is an aggressive form of skin cancer with a high prevalence in the population. An early diagnosis is crucial to cure this disease. Still, when this is not possible, combining potent pharmacological agents and effective drug delivery systems is essential to achieve optimal treatment and improve patients’ quality of life. Nanotechnology application in biomedical sciences to encapsulate anticancer drugs, including flavonoids, in order to enhance therapeutic efficacy has attracted particular interest. Flavonoids have shown effectiveness against various types of cancers including in melanoma, but they show low aqueous solubility, low stability and very poor oral bioavailability. The utilization of novel drug delivery systems could increase flavonoid bioavailability, thereby potentiating its antitumor effects in melanoma. This review summarizes the potential of different flavonoids in melanoma treatment and the several nanosystems used to improve their biological activity, considering published information that reported improved biological and pharmacological properties of encapsulated flavonoids. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Figure 1

23 pages, 5565 KiB

Open AccessReview

Molecularly Imprinted Polymer-Coated Inorganic Nanoparticles: Fabrication and Biomedical Applications

by Sinem Orbay, Ozgur Kocaturk, Rana Sanyal and Amitav Sanyal

Micromachines 2022, 13(9), 1464; https://doi.org/10.3390/mi13091464 - 3 Sep 2022

Cited by 17 | Viewed by 3397

Abstract

Molecularly imprinted polymers (MIPs) continue to gain increasing attention as functional materials due to their unique characteristics such as higher stability, simple preparation, robustness, better binding capacity, and low cost. In particular, MIP-coated inorganic nanoparticles have emerged as a promising platform for various [...] Read more.

Molecularly imprinted polymers (MIPs) continue to gain increasing attention as functional materials due to their unique characteristics such as higher stability, simple preparation, robustness, better binding capacity, and low cost. In particular, MIP-coated inorganic nanoparticles have emerged as a promising platform for various biomedical applications ranging from drug delivery to bioimaging. The integration of MIPs with inorganic nanomaterials such as silica (SiO₂), iron oxide (Fe₃O₄), gold (Au), silver (Ag), and quantum dots (QDs) combines several attributes from both components to yield highly multifunctional materials. These materials with a multicomponent hierarchical structure composed of an inorganic core and an imprinted polymer shell exhibit enhanced properties and new functionalities. This review aims to provide a general overview of key recent advances in the fabrication of MIPs-coated inorganic nanoparticles and highlight their biomedical applications, including drug delivery, biosensor, bioimaging, and bioseparation. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Figure 1

15 pages, 2366 KiB

Open AccessFeature PaperEditor’s ChoiceReview

Supercritical Fluids and Nanoparticles in Cancer Therapy

by Iolanda De Marco

Micromachines 2022, 13(9), 1449; https://doi.org/10.3390/mi13091449 - 1 Sep 2022

Cited by 7 | Viewed by 1557

Abstract

Nanoparticles are widely used in the pharmaceutical industry due to their high surface-to-volume ratio. Among the many techniques used to obtain nanoparticles, those based on supercritical fluids ensure reduced dimensions, narrow particle size distributions, and a very low or zero solvent residue in [...] Read more.

Nanoparticles are widely used in the pharmaceutical industry due to their high surface-to-volume ratio. Among the many techniques used to obtain nanoparticles, those based on supercritical fluids ensure reduced dimensions, narrow particle size distributions, and a very low or zero solvent residue in the powders. This review focuses on using supercritical carbon dioxide-based processes to obtain the nanoparticles of compounds used for the treatment or prevention of cancer. The scientific literature papers have been classified into two groups: nanoparticles consisting of a single active principle ingredient (API) and carrier/API nanopowders. Various supercritical carbon dioxide (scCO₂) based techniques for obtaining the nanoparticles were considered, along with the operating conditions and advantages and disadvantages of each process. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Figure 1

34 pages, 4434 KiB

Open AccessReview

Chitosan Nanoparticle Encapsulation of Antibacterial Essential Oils

by Arvind Negi and Kavindra Kumar Kesari

Micromachines 2022, 13(8), 1265; https://doi.org/10.3390/mi13081265 - 6 Aug 2022

Cited by 48 | Viewed by 7521

Abstract

Chitosan is the most suitable encapsulation polymer because of its natural abundance, biodegradability, and surface functional groups in the form of free NH₂ groups. The presence of NH₂ groups allows for the facile grafting of functionalized molecules onto the chitosan surface, [...] Read more.

Chitosan is the most suitable encapsulation polymer because of its natural abundance, biodegradability, and surface functional groups in the form of free NH₂ groups. The presence of NH₂ groups allows for the facile grafting of functionalized molecules onto the chitosan surface, resulting in multifunctional materialistic applications. Quaternization of chitosan’s free amino is one of the typical chemical modifications commonly achieved under acidic conditions. This quaternization improves its ionic character, making it ready for ionic–ionic surface modification. Although the cationic nature of chitosan alone exhibits antibacterial activity because of its interaction with negatively-charged bacterial membranes, the nanoscale size of chitosan further amplifies its antibiofilm activity. Additionally, the researcher used chitosan nanoparticles as polymeric materials to encapsulate antibiofilm agents (such as antibiotics and natural phytochemicals), serving as an excellent strategy to combat biofilm-based secondary infections. This paper provided a summary of available carbohydrate-based biopolymers as antibiofilm materials. Furthermore, the paper focuses on chitosan nanoparticle-based encapsulation of basil essential oil (Ocimum basilicum), mandarin essential oil (Citrus reticulata), Carum copticum essential oil (“Ajwain”), dill plant seed essential oil (Anethum graveolens), peppermint oil (Mentha piperita), green tea oil (Camellia sinensis), cardamom essential oil, clove essential oil (Eugenia caryophyllata), cumin seed essential oil (Cuminum cyminum), lemongrass essential oil (Cymbopogon commutatus), summer savory essential oil (Satureja hortensis), thyme essential oil, cinnamomum essential oil (Cinnamomum zeylanicum), and nettle essential oil (Urtica dioica). Additionally, chitosan nanoparticles are used for the encapsulation of the major essential components carvacrol and cinnamaldehyde, the encapsulation of an oil-in-water nanoemulsion of eucalyptus oil (Eucalyptus globulus), the encapsulation of a mandarin essential oil nanoemulsion, and the electrospinning nanofiber of collagen hydrolysate–chitosan with lemon balm (Melissa officinalis) and dill (Anethum graveolens) essential oil. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Figure 1

16 pages, 4018 KiB

Open AccessReview

Cashew Gum: A Review of Brazilian Patents and Pharmaceutical Applications with a Special Focus on Nanoparticles

by Ricardo G. Amaral, Lucas R. Melo de Andrade, Luciana N. Andrade, Kahynna C. Loureiro, Eliana B. Souto and Patrícia Severino

Micromachines 2022, 13(7), 1137; https://doi.org/10.3390/mi13071137 - 18 Jul 2022

Cited by 12 | Viewed by 2607

Abstract

Natural polysaccharides are structures composed of highly diversified biological macromolecules whose properties have been exploited by a diversity of industries. Until 2018, the polysaccharides market raised more than US $ 12 billion worldwide, while an annual growth forecast of 4.8% is expected by [...] Read more.

Natural polysaccharides are structures composed of highly diversified biological macromolecules whose properties have been exploited by a diversity of industries. Until 2018, the polysaccharides market raised more than US $ 12 billion worldwide, while an annual growth forecast of 4.8% is expected by 2026. The food industry is largely responsible for the consumption of this plant-source material, produced by microbiological fermentation. Among the used polysaccharides, gums are hydrocolloids obtained from a variety of sources and in different forms, being composed of salts of calcium, potassium, magnesium and sugar monomers. Their non-toxicity, hydrophilicity, viscosity, biodegradability, biocompatibility and sustainable production are among their main advantages. Although Brazil is amongst the largest producers of cashew gum, reaching 50 tons per year, the polysaccharide is not being used to its full potential, in particular, with regard to its uses in pharmaceuticals. Cashew gum (CG), obtained from Anacardium occidentale L., caught the attention of the industry only in 1970; in 1990, its production started to grow. Within the Brazilian academy, the groups from the Federal University of Ceará and Piauí are devoting the most efforts to the study of cashew gum, with a total of 31 articles already published. The number of patents in the country for innovations containing cashew tree gum has reached 14, including the technological process for the purification of cashew tree gum, comparison of physical and chemical methods for physicochemical characterizations, and optimum purification methodology. This scenario opens a range of opportunities for the use of cashew gum, mainly in the development of new pharmaceutical products, with a special interest in nanoparticles. Full article

(This article belongs to the Special Issue Nanoparticles in Biomedical Sciences)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Nanoparticles in Biomedical Sciences

Share This Special Issue

Special Issue Editors

Special Issue Information

Keywords

Benefits of Publishing in a Special Issue

Published Papers (24 papers)

Research

Review

Further Information

Guidelines

MDPI Initiatives

Follow MDPI