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Keywords = SERS molecule positioning

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32 pages, 26755 KB  
Article
Novel Sulfonate Derivatives Functionalized with Triazole–Hydrazone Moieties: Synthesis, Characterization, DFT, Targeting Brain Tumors via DNA Damage, Cytotoxicity, Migration Suppression, Antimicrobial Activity, and In Silico Study
by Yasemin Ünver, Meryem Evecen, Fatih Çelik, Ali Aydın, Halil İbrahim Güler, Kadriye İnan Bektaş and Tuğba Usta
Molecules 2026, 31(13), 2281; https://doi.org/10.3390/molecules31132281 - 30 Jun 2026
Viewed by 222
Abstract
In this study, a new series of (E)-4-((2-(2-(4-amino-3-methyl-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl)acetyl)hydrazono)methyl)phenyl 4-halogenobenzenesulfonates (3a3d), where 3a = F, 3b = Cl, 3c = Br, and 3d = I, were successfully synthesized via a straightforward synthetic route. The structures of the obtained compounds were [...] Read more.
In this study, a new series of (E)-4-((2-(2-(4-amino-3-methyl-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl)acetyl)hydrazono)methyl)phenyl 4-halogenobenzenesulfonates (3a3d), where 3a = F, 3b = Cl, 3c = Br, and 3d = I, were successfully synthesized via a straightforward synthetic route. The structures of the obtained compounds were fully characterized and confirmed by spectroscopic techniques, including FT-IR, 1H NMR, and 13C NMR, as well as LC-MS/MS analysis. 1,2,4-triazole-based hydrazone derivatives (3a3d) were investigated using IR and NMR spectroscopy and DFT calculations. Intermolecular interactions, HOMO-LUMO, dipole moment, polarization, first-order hyperpolarizability, and molecular electrostatic potential studies on the molecules were examined. The HOMO and LUMO energy gap study supports the charge transfer probability in the molecules. These were conducted to investigate the reactivity and stability of heterocyclic molecules in bioactivity analysis. Electron density mapping within the molecular electrostatic potential plot and electrostatic potential representation within the iso-surface plot evaluated the concept of charge distribution in the molecule as nucleophilic reactions and electrophilic regions. The predicted nonlinear optical (NLO) properties of the molecules are much greater than those of urea. The results obtained from these investigations collectively provide evidence that the molecules possess nonlinear optical applications. Novel triazole–hydrazone-functionalized aryl sulfonate derivatives (3a3d) were evaluated for their anticancer potential against a panel of brain and non-brain cancer cell lines. Compound 3b exhibited the most favorable overall biological profile, displaying potent activity against SH-SY5Y neuroblastoma (GI = 7.59 μM) and U87MG glioblastoma cells (GI = 13.85 μM), together with the lowest toxicity toward normal FL fibroblasts (GI = 62.02 μM). Compounds 3c and 3d demonstrated remarkable potency against IDHmut-U87 glioma cells (GI = 3.87 and 3.27 μM, respectively), although their selectivity toward cancer cells was limited. DNA degradation studies revealed substantial fragmentation, particularly in C6 and SH-SY5Y cells, while migration assays indicated reduced cellular motility. Molecular docking studies identified compound 3b as the strongest PI3Kα binder, supporting a possible. In addition, the antimicrobial activities of compounds 3a3d were evaluated against selected Gram-positive and Gram-negative bacteria as well as Candida species using the broth microdilution method. The compounds exhibited measurable antimicrobial effects with MIC values ranging from 156 to 625 µg/mL, showing moderate growth inhibition against the tested microorganisms. Although the observed activity was lower than that of the reference antimicrobial agents, the results indicate that these triazole–hydrazone derivatives possess a detectable level of antimicrobial activity and provide a basis for further structural optimization. Collectively, the results suggest that compound 3b represents the most promising lead structure due to its balanced combination of potency, selectivity, and predicted target engagement. Molecular docking was performed to evaluate the binding potential of newly synthesized triazole derivatives (3a3d) against PI3Kα. The docking protocol was validated by re-docking alpelisib, yielding an RMSD of 0.64 Å. Among the tested compounds, 3b showed the most favorable binding energy (−9.94 kcal/mol) and estimated Ki value (52.13 nM), consistent with its superior in vitro activity. Its interactions with key PI3Kα residues, including Val851, Ser854, Met922, and Asp933, support a stable binding mode within the ATP-binding pocket. In silico ADME and toxicity analyses suggested acceptable drug-likeness characteristics, absence of major hepatotoxic, mutagenic, and carcinogenic liabilities, and moderate predicted acute toxicity profiles. These findings suggest that 3b is the most promising derivative for further validation. Full article
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75 pages, 12547 KB  
Review
Next-Generation SERS Probes: Engineering Hotspots, Intelligent Molecular Targeting, and AI-Driven Spectral Analysis for Emerging Applications
by Unmanaa Dewanjee, Shi Bai, Yury V. Ryabchikov, David Fieser, Sharma Pradakshina, Jie Jayne Wu, Marco Fronzi and Anming Hu
Nanomaterials 2026, 16(10), 628; https://doi.org/10.3390/nano16100628 - 19 May 2026
Viewed by 791
Abstract
Surface-enhanced Raman spectroscopy (SERS) has evolved from a fundamental optical phenomenon to a powerful, molecule-specific analytical technique capable of detecting ultra-trace-level species across biomedicine, catalysis, environmental monitoring, and national security applications. In this review, we summarize recent advances in SERS probe design and [...] Read more.
Surface-enhanced Raman spectroscopy (SERS) has evolved from a fundamental optical phenomenon to a powerful, molecule-specific analytical technique capable of detecting ultra-trace-level species across biomedicine, catalysis, environmental monitoring, and national security applications. In this review, we summarize recent advances in SERS probe design and fabrication along three major directions: (i) engineering plasmonic hotspots with enhanced field confinement to achieve stronger and more uniform signals; (ii) analyte-directed strategies that precisely position and retain target molecules via tailored surface chemistries, nanoscale confinement, and on-surface reactions for single hotspot SERS; and (iii) hybrid architectures integrating plasmonic metals with functional materials, including high entropy materials, semiconductors, and graphene and other 2D materials, to synergistically couple electromagnetic and chemical enhancement mechanisms. Despite significant progress, key challenges remain for practical applications outside laboratories, including substrate reproducibility and stability, diverse analyte compatibility, unknown molecule identification and standardized quantitative performance in complex environments. We highlight emerging solutions, such as large-area nanomanufacturing for controlled nanoscale gaps, high-resolution Raman mapping for spatial–temporal characterization, density-functional-theory-guided molecular interpretation, and machine-learning-enabled spectral analysis. Advances in foundational AI models and data-driven discovery are positioning SERS to become an increasingly versatile platform, from decoding unknown molecular structures to analyzing complicated multi-component systems for environmental, biomedical, and national security applications with high sensitivity and selectivity. Full article
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18 pages, 4724 KB  
Article
Raman and SERS Spectra of Human Myelin Basic Protein in Cerebrospinal Fluid
by Antonio Bravo-Oro, Sergio Ugarte-Anchondo, Erick Osvaldo Martínez-Ruiz, Ma. del Carmen Rodríguez-Aranda, Adán Reyes-Reyes, Cristian Israel García-Mendoza, Luis Carlos Ortiz-Dosal, Emmanuel Rivera-Pérez, Juan Andrés Reyes-Reyes, Eleazar Samuel Kolosovas-Machuca and Alejandra Ortiz-Dosal
Nanomaterials 2026, 16(10), 594; https://doi.org/10.3390/nano16100594 - 12 May 2026
Viewed by 1177
Abstract
Raman spectroscopy (RS) provides detailed information on molecular structure but remains challenging for low-scattering proteins in complex media. Myelin basic protein (MBP) is a key structural component of central nervous system myelin and a clinically relevant molecule in demyelinating disorders; however, to the [...] Read more.
Raman spectroscopy (RS) provides detailed information on molecular structure but remains challenging for low-scattering proteins in complex media. Myelin basic protein (MBP) is a key structural component of central nervous system myelin and a clinically relevant molecule in demyelinating disorders; however, to the best of our knowledge, its Raman signature in solution has not been reported. In this work, Raman and surface-enhanced Raman spectroscopy (SERS) were employed to characterize purified human myelin basic protein (MBP) in aqueous solution and cerebrospinal fluid (CSF). Quasi-spherical silver nanoparticles were used as SERS elements, yielding enhancement factors of 105 and increasing sensitivity to MBP-associated spectral changes at low concentrations. The MBP spectrum exhibited vibrational modes primarily associated with amide II and amide III bands, as well as aromatic side-chain contributions. Comparative analysis of MBP, CSF, and MBP-spiked CSF samples revealed significant spectral overlap, limiting discrimination based solely on peak positions. To overcome this limitation, spectral correlation and band-intensity-ratio analyses were applied, revealing reproducible trends associated with increasing MBP content. While individual MBP bands are not exclusive, the observed spectral patterns demonstrate the sensitivity of RS and SERS to MBP-induced spectral changes in CSF. These findings should be interpreted as a proof-of-concept in a single-donor CSF matrix. Full article
(This article belongs to the Section Biology and Medicines)
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12 pages, 2884 KB  
Article
Aluminum-Induced Surface-Enhanced Raman Scattering in Ti-Al-Ti Sandwich Multilayer Thin Films
by Luping Wu, Tingzhen Yan, Ruijin Hong, Chunxian Tao, Qi Wang, Hui Lin and Zhaoxia Han
Nanomaterials 2026, 16(3), 216; https://doi.org/10.3390/nano16030216 - 6 Feb 2026
Viewed by 734
Abstract
A series of Ti-Al-Ti sandwich thin films with different Al layer thicknesses was prepared via magnetron sputtering. The Al layer facilitated Ti-Al metal coupling within the films, which significantly strengthened the localized surface plasmon resonance (LSPR) and obtained more “hot-spots”, ultimately leading to [...] Read more.
A series of Ti-Al-Ti sandwich thin films with different Al layer thicknesses was prepared via magnetron sputtering. The Al layer facilitated Ti-Al metal coupling within the films, which significantly strengthened the localized surface plasmon resonance (LSPR) and obtained more “hot-spots”, ultimately leading to a remarkable enhancement of the localized electric field. The LSPR effectively promoted charge transfer between probe molecules and the Ti-Al-Ti sandwich thin film. Raman scattering intensity was jointly governed by chemical and electromagnetic enhancement mechanisms. When used as a surface-enhanced Raman scattering (SERS) substrate for methylene blue (MB) detection, the sandwich-structured films achieved a Raman enhancement factor of 3.27 × 106, approximately twice that of single-layer silver thin films. The substrate exhibited a low MB detection limit for MB of 10−8 M and excellent stability. Additionally, the relative standard deviation of main characteristic peak intensities across different positions is consistently below 6%, indicating superior uniformity and reproducibility. Experimental results are in good agreement with FDTD simulation outcomes. Full article
(This article belongs to the Section Nanocomposite Materials)
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13 pages, 2429 KB  
Article
Mitochondrial Genome Features and Phylogenetic Analyses of Four Chrysochroinae Species (Coleoptera: Buprestidae)
by Jieqiong Wang, Yingying Li, Zhonghua Wei and Aimin Shi
Biomolecules 2025, 15(11), 1531; https://doi.org/10.3390/biom15111531 - 30 Oct 2025
Viewed by 850
Abstract
The number of known mitochondrial genomes in Buprestidae is limited, especially in Chrysochroinae, which seriously hinders the phylogenetic study of this family. The mitogenomes of Capnodis miliaris, Lamprodila cupreosplendens, Sphenoptera insidiosa and Philocteanus rubroaureus were sequenced, assembled and annotated in this [...] Read more.
The number of known mitochondrial genomes in Buprestidae is limited, especially in Chrysochroinae, which seriously hinders the phylogenetic study of this family. The mitogenomes of Capnodis miliaris, Lamprodila cupreosplendens, Sphenoptera insidiosa and Philocteanus rubroaureus were sequenced, assembled and annotated in this study. The mitogenomes of these four species are typical circular double-stranded DNA molecules, containing 13 protein-coding genes (PCGS), 22 transfer RNA genes (tRNAs), 2 ribosomal RNA genes (rRNAs), and a control region (CR). The total lengths of these four mitogenomes are moderate, ranging from 15,778 bp to 16,230 bp. Additionally, their A + T content ranges from 68.76% to 73.47%, showing positive AT-skew values ranging from 0.098 to 0.181. Relative Synonymous Codon Usage (RSCU) analysis indicated that TTT (Phe), ATT (Ile), TCT (Ser2), and TTA (Leu2) are the most frequently used codons. The gene arrangement of four mitogenomes is consistent with the previously reported Buprestidae mitogenomes. Most of the PCGs use ATN as the start codon, with TAA as the stop codon or an incomplete stop codon T-. Phylogenetic trees were constructed based on the PCGs and rRNAs using both maximum-likelihood and Bayesian inference methods. The phylogenetic results showed that Julodinae, Polycestinae, Buprestinae and Agrilinae are monophyletic groups, and Chrysochroinae is a paraphyletic group. As the number of Buprestidae mitogenomes used for polyogenetic analysis increases, the topology of phylogenetic tree shows differences compared to previous studies. Full article
(This article belongs to the Section Molecular Biology)
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36 pages, 2877 KB  
Article
Dual-Oriented Targeted Nanostructured SERS Label-Free Immunosensor for Detection, Quantification, and Analysis of Breast Cancer Biomarker Concentrations in Blood Serum
by Mohammad E. Khosroshahi, Christine Gaoiran, Vithurshan Umashanker, Hayagreev Veeru and Pranav Panday
Biosensors 2025, 15(7), 447; https://doi.org/10.3390/bios15070447 - 11 Jul 2025
Cited by 3 | Viewed by 1694
Abstract
In clinical applications of surface-enhanced Raman spectroscopy (SERS) immunosensors, accurately determining analyte biomarker concentrations is essential. This study presents a non-invasive approach for quantifying various breast cancer biomarkers—including human epidermal growth factor receptor II (HER-II) (2+, 3+ (I), 3+ (II), 3+ (III), and [...] Read more.
In clinical applications of surface-enhanced Raman spectroscopy (SERS) immunosensors, accurately determining analyte biomarker concentrations is essential. This study presents a non-invasive approach for quantifying various breast cancer biomarkers—including human epidermal growth factor receptor II (HER-II) (2+, 3+ (I), 3+ (II), 3+ (III), and positive IV) and CA 15-3—using a directional, plasmonically active, label-free SERS sensor. Each stage of sensor functionalization, conjugation, and biomarker interaction was verified by UV–Vis spectroscopy. Atomic force microscopy (AFM) characterized the morphology of gold nanourchin (GNU)-immobilized printed circuit board (PCB) substrates. An enhancement factor of ≈ 0.5 × 105 was achieved using Rhodamine 6G as the probe molecule. Calibration curves were initially established using standard HER-II solutions at concentrations ranging from 1 to 100 ng/mL and CA 15-3 at concentrations from 10 to 100 U/mL. The SERS signal intensities in the 620–720 nm region were plotted against concentration, yielding linear sensitivity with R2 values of 0.942 and 0.800 for HER-II and CA15-3, respectively. The same procedure was applied to breast cancer serum (BCS) samples, allowing unknown biomarker concentrations to be determined based on the corresponding calibration curves. SERS data were processed using the filtfilt filter from scipy.signal for smoothing and then baseline-corrected with the Improved Asymmetric Least Squares (IASLS) algorithm from the pybaselines.Whittaker library. Principal Component Analysis (PCA) effectively distinguished the sample groups and revealed spectral differences before and after biomarker interactions. Key Raman peaks were attributed to functional groups including N–H (primary and secondary amines), C–H antisymmetric stretching, C–N (amines), C=O antisymmetric stretching, NH3+ (amines), carbohydrates, glycine, alanine, amides III, C=N stretches, and NH2 in primary amides. Full article
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20 pages, 5356 KB  
Article
Structure–Function Analysis of the Steroid-Hydroxylating Cytochrome P450 109 (CYP109) Enzyme Family
by Siphesihle M. Msweli, Tiara Padayachee, Thembeka Khumalo, David R. Nelson, David C. Lamb and Khajamohiddin Syed
Int. J. Mol. Sci. 2025, 26(13), 6219; https://doi.org/10.3390/ijms26136219 - 27 Jun 2025
Cited by 4 | Viewed by 2099
Abstract
Steroids are found in bacteria and eukaryotes, and genes potentially encoding steroid metabolic enzymes have also been identified in giant viruses. For decades, hydroxylated steroids have been utilized in medicine to treat various human diseases. The hydroxylation of steroids can be achieved using [...] Read more.
Steroids are found in bacteria and eukaryotes, and genes potentially encoding steroid metabolic enzymes have also been identified in giant viruses. For decades, hydroxylated steroids have been utilized in medicine to treat various human diseases. The hydroxylation of steroids can be achieved using microbial enzymes, especially cytochrome P450 monooxygenases (CYPs/P450s) and is well documented. Understanding the structural determinants that govern the regio- and stereoselectivity of steroid hydroxylation by P450s is essential in order to fully exploit their potential. Herein, we present a comprehensive analysis of the steroid-hydroxylating CYP109 family across the domains of life and delineate the structural determinants that govern steroid hydroxylation. Data mining, annotation, and phylogenetic analysis revealed that CYP109 family members are highly populated in bacteria, and indeed, these members passed from bacteria to archaea by horizontal gene transfer, leading to the evolution of P450s in archaea. Analysis of twelve CYP109 crystal structures revealed large, flexible, and dynamic active site cavities that can accommodate multiple ligands. The correct positioning and orientation of the steroid in the active site cavity and the nature of the C17 substituent on the steroid molecule influence catalysis. In an analogous fashion to the CYP107 family, the amino acid residues within the CYP109 binding pocket involve hydrophilic and hydrophobic interactions, influencing substrate orientations and anchoring and determining the site of hydroxylation and catalytic activity. A handful of amino acids, such as Val84, Val292, and Ser387 in CYP109B4, have been found to play a role in determining the catalytic regiospecificity, and a single amino acid, such as Arg74 in CYP109A2, has been found to be essential for the enzymatic activity. This work serves as a reference for the precise understanding of CYP109 structure–function relationships and for P450 enzymes in general. The findings will guide the genetic engineering of CYP109 enzymes to produce valuable steroid molecules of medicinal and biotechnological importance. Full article
(This article belongs to the Section Biochemistry)
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15 pages, 1212 KB  
Article
New Temporin A Analogues Modified in Positions 1 and 10—Synthesis and Biological Studies
by Dilyana Dimitrova, Veronica Nemska, Ivan Iliev, Stoyko Petrin, Nelly Georgieva and Dancho Danalev
Pharmaceutics 2025, 17(4), 396; https://doi.org/10.3390/pharmaceutics17040396 - 21 Mar 2025
Cited by 2 | Viewed by 1650
Abstract
Background/Objectives: With growing antimicrobial resistance, the overuse of antibiotics, and stagnation in the discovery of new antibiotics, a novel alternative is required to overcome hard-to-treat infections. Antimicrobial peptides (AMPs) show great potential as a possible alternative to standard chemotherapeutics. Temporins are a [...] Read more.
Background/Objectives: With growing antimicrobial resistance, the overuse of antibiotics, and stagnation in the discovery of new antibiotics, a novel alternative is required to overcome hard-to-treat infections. Antimicrobial peptides (AMPs) show great potential as a possible alternative to standard chemotherapeutics. Temporins are a group of AMPs that have been under the spotlight in numerous studies. Herein, we report the design and synthesis of Temporin A modified in position 1, where the proteinogenic amino acid Phe is replaced by Tyr or fluorinated Phe. In addition, in other analogues, in position 10, the Ser residue is replaced by Tyr or Thr. The aim of all modifications in the primary structure of the native Temporin A is to study the influence of the changes made on the antibacterial properties, antiproliferative activity, and hydrolytic stability of the newly synthesized molecules. Methods: The Fmoc/OBut SPPS strategy was employed for the synthesis of the novel-designed analogues. The antibacterial activity was evaluated with both disk diffusion and broth microdilution methods. The BALB 3T3 NRU test and MTT dye reduction assay were used to determine safety and antiproliferative activity. Results: The investigated analogues have low toxicity and are photosafe. The greatest selectivity was shown by DTTyr10 towards MCF-7 cells. DT4F, containing fluorinated Phe in position 1, was the most effective antibacterial agent among the new compounds. The incorporation of Thr in position 10, in comparison with the natural Ser residue, led to an increase in the antiproliferative effect of the new peptide. Conclusions: The obtained structure–activity relationship data show that the most promising compound in the tested series is FLPLIGRVL-Y-GILNH2, where the Ser residue in position 10 is replaced by a more hydrophobic OH-containing Tyr residue. The analogue containing fluorinated Phe in position 1, DT4F, has the highest antiproliferative effect against both tested tumor cell lines, combined with good antibacterial properties at the lowest MIC (80 µg/mL), but it is more cyto- and phototoxic than the parent DTA molecule and is not stable at pH 9 for a 24 h period. Full article
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16 pages, 2872 KB  
Article
Encapsulation of Vecuronium and Rocuronium by Sugammadex Investigated by Surface-Enhanced Raman Spectroscopy
by Adriana Kenđel, Ivo Piantanida and Snežana Miljanić
Molecules 2025, 30(2), 231; https://doi.org/10.3390/molecules30020231 - 9 Jan 2025
Cited by 3 | Viewed by 2952
Abstract
Aiming toward a novel, noninvasive technique, with a real-time potential application in the monitoring of the complexation of steroidal neuromuscular blocker drugs Vecuronium (Vec) and Rocuronium (Roc) with sugammadex (SDX, medication for the reversal of neuromuscular blockade [...] Read more.
Aiming toward a novel, noninvasive technique, with a real-time potential application in the monitoring of the complexation of steroidal neuromuscular blocker drugs Vecuronium (Vec) and Rocuronium (Roc) with sugammadex (SDX, medication for the reversal of neuromuscular blockade induced by Vec or Roc in general anesthesia), we developed proof-of-principle methodology based on surface-enhanced Raman spectroscopy (SERS). Silver nanoparticles prepared by the reduction of silver ions with hydroxylamine hydrochloride were used as SERS-active substrates, additionally aggregated with calcium nitrate as needed. The Vec and Roc SERS spectra were obtained within the biorelevant 5 × 10−7–1 × 10−4 M range, as well as the SERS of SDX, though the latter was observed only in the presence of the aggregating agent. SDX/drug complexes at a 1/1 molar ratio revealed significant spectral changes in the vibrational bands of the SDX glucose rings and the drug steroid rings, implying that the insertion of Vec and Roc molecules into the SDX cavity was not only driven by attractive electrostatic interactions between the positively charged cyclic unit of the drug and the negative carboxylate groups of cyclodextrin but also supported by hydrophobic interactions between the host cyclodextrin and the guest drug molecule. The observed changes in SERS signals are applicable in biorelevant conditions and support further studies of SDX/drug complexes in vivo. Full article
(This article belongs to the Section Analytical Chemistry)
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11 pages, 2121 KB  
Article
A Tuneable and Easy-to-Prepare SERS Substrate Based on Ag Nanorods: A Versatile Tool for Solution and Dry-State Analyses
by Margherita Longoni, Sofia Zucca and Silvia Bruni
Nanomaterials 2024, 14(22), 1808; https://doi.org/10.3390/nano14221808 - 11 Nov 2024
Cited by 1 | Viewed by 2480
Abstract
Surface-enhanced Raman spectroscopy is a powerful technique for the ultra-sensitive detection of organic analytes. In this paper, the preparation of SERS substrates based on silver nanorods (AgNRs) is proposed, exploiting a simple protocol which does not require complex procedures and/or sophisticated and expensive [...] Read more.
Surface-enhanced Raman spectroscopy is a powerful technique for the ultra-sensitive detection of organic analytes. In this paper, the preparation of SERS substrates based on silver nanorods (AgNRs) is proposed, exploiting a simple protocol which does not require complex procedures and/or sophisticated and expensive instrumentation. For this purpose, various syntheses of AgNRs were tested, and the best one for preparing the SERS active substrate proved to be the one which does not involve surfactants as nanoparticle stabilizers. The plasmonic properties of the selected substrate can be modified based on the concentration of the deposited nanoparticles, allowing for the experimentation of different excitation wavelengths. Positive results were obtained on reference solutions of three natural dyes of historical interest using both green exciting radiation (532 nm) and two near-infrared ones (785 and 850 nm; the latter is combined with the SSE™ technology for further fluorescence quenching). Furthermore, the substrates of AgNRs were found to be suitable for SERS measurements even in dry-state conditions, i.e., only exploiting the electromagnetic interaction between the nanostructured substrate and the dye molecules absorbed onto a wool fibre. Full article
(This article belongs to the Special Issue Nanomaterial-Based SERS Sensing and Detection Technology)
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14 pages, 6874 KB  
Article
Fabrication of Large-Area High-Resolution Templates by Focused Ion Beam Combined with Colloidal Nanoparticle Dimer Deposition for SERS Substrates
by Liga Ignatane, Reinis Ignatans, Juris Prikulis, Annamarija Trausa, Ciro Federico Tipaldi, Edgars Vanags, Martins Zubkins, Krisjanis Smits and Anatolijs Sarakovskis
Nanomaterials 2024, 14(22), 1784; https://doi.org/10.3390/nano14221784 - 6 Nov 2024
Cited by 5 | Viewed by 2370
Abstract
This article presents an examination of well-controlled patterns created using a Ga+-based focused ion beam (FIB) on glass, while silicon substrates were used to evaluate the FIB performance by its achievable feature size versus time constraints. The pattern creation on glass [...] Read more.
This article presents an examination of well-controlled patterns created using a Ga+-based focused ion beam (FIB) on glass, while silicon substrates were used to evaluate the FIB performance by its achievable feature size versus time constraints. The pattern creation on glass was developed with the aim of studying potential surface-enhanced Raman spectroscopy (SERS) applications. Furthermore, the FIB was used to create dimer systems of periodically and randomly positioned dumbbell-shaped pits on the glass (each dimer occupies an area of 203 × 87 nm2). By following the bitmap pattern files, the FIB ensured there was 3000 dimer fabrication over a 20 × 20 μm2 large area, with a pit size and position variation below 10 nm. The article highlights that FIB can be used for precise large-area nano-fabrication. The gold nanoparticle dimers were formed on the prepatterned surface via capillary force-assisted deposition. The fabricated nanostructures were tested in SERS measurements. The enhancement factor for Rhodamine B molecule reached ~105, demonstrating the potential application of the method to create nanostructures in the sensor domain. Full article
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17 pages, 3465 KB  
Article
Hair Growth-Promoting Effect of Hydrangea serrata (Thunb.) Ser. Extract and Its Active Component Hydrangenol: In Vitro and In Vivo Study
by Soyoon Park, Hyunjae Kim, Hye Shin Ahn, Changseon Na and Yu-Kyong Shin
Int. J. Mol. Sci. 2024, 25(19), 10370; https://doi.org/10.3390/ijms251910370 - 26 Sep 2024
Cited by 3 | Viewed by 5876
Abstract
With the escalating prevalence of hair loss, the demand for effective hair loss treatment has surged. This study evaluated the effects of hot water extract of Hydrangea serrata (Thunb.) Ser. leaf (WHS) on hair growth, employing cell cultures, mice, and human skin organoid [...] Read more.
With the escalating prevalence of hair loss, the demand for effective hair loss treatment has surged. This study evaluated the effects of hot water extract of Hydrangea serrata (Thunb.) Ser. leaf (WHS) on hair growth, employing cell cultures, mice, and human skin organoid models. Both WHS and hydrangenol were found to enhance 5α-reductase inhibitory activity. WHS and hydrangenol have been shown to stimulate dermal papilla cell (DPC) growth, potentially through factors like keratinocyte growth factor (KGF), fibroblast growth factor 10 (FGF10), and transforming growth factor-β1 (TGF-β1). They also elevated the expression levels of keratin genes (K31 and K85) and the ceramide synthase (CerS3) gene, crucial clinical indicators of hair health. Furthermore, they exhibited notable anti-inflammatory and anti-androgenic properties by reducing the levels of tumor necrosis factor-α (TNF-α) and androgen signaling molecules, including androgen receptor (AR) and dickkopf-1 (DKK-1) gene expression. Oral administration of WHS to C57BL/6 mice for 3 weeks confirmed its hair growth-promoting effects, improving hair growth parameters and gene expression without significant changes in hair weight. Additionally, in a human skin organoid model, WHS was found to stimulate hair formation and augment the expression of follicle markers. These findings position WHS as a promising nutraceutical for promoting hair health, as evidenced by its efficacy in both in vitro and in vivo models. Full article
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15 pages, 3006 KB  
Article
Structural and Mechanistic Insights into a Novel Monooxygenase for Poly(acrylic acid) Biodegradation
by Rui Feng, Juyi Zhao, Xiaochen Li, Sijun Dong and Dan Ma
Int. J. Mol. Sci. 2024, 25(16), 8871; https://doi.org/10.3390/ijms25168871 - 15 Aug 2024
Cited by 4 | Viewed by 2024
Abstract
Polyacrylamide (PAM) is a high-molecular-weight polymer with extensive applications. However, the inefficient natural degradation of PAM results in environmental accumulation of the polymer. Biodegradation is an environmentally friendly approach in the field of PAM treatment. The first phase of PAM biodegradation is the [...] Read more.
Polyacrylamide (PAM) is a high-molecular-weight polymer with extensive applications. However, the inefficient natural degradation of PAM results in environmental accumulation of the polymer. Biodegradation is an environmentally friendly approach in the field of PAM treatment. The first phase of PAM biodegradation is the deamination of PAM, forming the product poly(acrylic acid) (PAA). The second phase of PAM biodegradation involves the cleavage of PAA into small molecules, which is a crucial step in the degradation pathway of PAM. However, the enzyme that catalyzes the degradation of PAA and the molecular mechanism remain unclear. Here, a novel monooxygenase PCX02514 is identified as the key enzyme for PAA degradation. Through biochemical experiments, the monooxygenase PCX02514 oxidizes PAA with the participation of NADPH, causing the cleavage of carbon chains and a decrease in the molecular weight of PAA. In addition, the crystal structure of the monooxygenase PCX02514 is solved at a resolution of 1.97 Å. The active pocket is in a long cavity that extends from the C-terminus of the TIM barrel to the protein surface and exhibits positive electrostatic potential, thereby causing the migration of oxygen-negative ions into the active pocket and facilitating the reaction between the substrates and monooxygenase PCX02514. Moreover, Arg10-Arg125-Ser186-Arg187-His253 are proposed as potential active sites in monooxygenase PCX02514. Our research characterizes the molecular mechanism of this monooxygenase, providing a theoretical basis and valuable tools for PAM bioremediation. Full article
(This article belongs to the Section Biochemistry)
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19 pages, 4993 KB  
Article
Nanosized Complexes of the Proteolytic Enzyme Serratiopeptidase with Cationic Block Copolymer Micelles Enhance the Proliferation and Migration of Human Cells
by Katya Kamenova, Anna Prancheva, Lyubomira Radeva, Krassimira Yoncheva, Maya M. Zaharieva, Hristo M. Najdenski and Petar D. Petrov
Pharmaceutics 2024, 16(8), 988; https://doi.org/10.3390/pharmaceutics16080988 - 25 Jul 2024
Cited by 5 | Viewed by 1901
Abstract
In this study, we describe the preparation of the cationic block copolymer nanocarriers of the proteolytic enzyme serratiopeptidase (SER). Firstly, an amphiphilic poly(2-(dimethylamino)ethyl methacrylate)-b-poly(ε-caprolactone)-b-poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA9-b-PCL35-b-PDMAEMA9) triblock copolymer was synthesized by reversible addition-fragmentation chain-transfer (RAFT) polymerization. Then, [...] Read more.
In this study, we describe the preparation of the cationic block copolymer nanocarriers of the proteolytic enzyme serratiopeptidase (SER). Firstly, an amphiphilic poly(2-(dimethylamino)ethyl methacrylate)-b-poly(ε-caprolactone)-b-poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA9-b-PCL35-b-PDMAEMA9) triblock copolymer was synthesized by reversible addition-fragmentation chain-transfer (RAFT) polymerization. Then, cationic micellar nanocarriers consisting of a PCL hydrophobic core and a PDMAEMA hydrophilic shell were formed by the solvent evaporation method. SER was loaded into the polymeric micelles by electrostatic interaction between the positively charged micellar shell and the negatively charged enzyme molecules. The particle size, zeta potential, and colloid stability of complexes as a function of SER concentration were investigated by dynamic and electrophoretic light scattering. It was found that SER retained its proteolytic activity after immobilization in polymeric carriers. Moreover, the complexes have a concentration-dependent enhancing effect on the proliferation and migration of human keratinocyte HaCaT and gingival fibroblast HGF cells. Full article
(This article belongs to the Special Issue Self-Assembled Amphiphilic Copolymers in Drug Delivery, 2nd Edition)
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Article
Studying the Interaction between Bendamustine and DNA Molecule with SERS Based on AuNPs/ZnCl2/NpAA Solid-State Substrate
by Lina Yao, Yanjie Li, Zhenzhong Zuo, Ziyi Gong, Jie Zhu, Xiaoqiang Feng, Dan Sun and Kaige Wang
Int. J. Mol. Sci. 2023, 24(17), 13517; https://doi.org/10.3390/ijms241713517 - 31 Aug 2023
Cited by 9 | Viewed by 2626
Abstract
Bendamustine (BENDA) is a bifunctional alkylating agent with alkylating and purinergic antitumor activity, which exerts its anticancer effects by direct binding to DNA, but the detailed mechanism of BENDA–DNA interaction is poorly understood. In this paper, the interaction properties of the anticancer drug [...] Read more.
Bendamustine (BENDA) is a bifunctional alkylating agent with alkylating and purinergic antitumor activity, which exerts its anticancer effects by direct binding to DNA, but the detailed mechanism of BENDA–DNA interaction is poorly understood. In this paper, the interaction properties of the anticancer drug BENDA with calf thymus DNA (ctDNA) were systematically investigated based on surface-enhanced Raman spectroscopy (SERS) technique mainly using a novel homemade AuNPs/ZnCl2/NpAA (NpAA: nano porous anodic alumina) solid-state substrate and combined with ultraviolet–visible spectroscopy and molecular docking simulation to reveal the mechanism of their interactions. We experimentally compared and studied the SERS spectra of ctDNA, BENDA, and BENDA–ctDNA complexes with different molar concentrations (1:1, 2:1, 3:1), and summarized their important characteristic peak positions, their peak position differences, and hyperchromic/hypochromic effects. The results showed that the binding modes include covalent binding and hydrogen bonding, and the binding site of BENDA to DNA molecules is mainly the N7 atom of G base. The results of this study help to understand and elucidate the mechanism of BENDA at the single-molecule level, and provide guidance for the further development of effective new drugs with low toxicity and side effects. Full article
(This article belongs to the Special Issue Applications of Raman Spectroscopy in Molecular Biology)
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