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Communications Biology Jan 2021The proliferation and transmission of viruses has become a threat to worldwide biosecurity, as exemplified by the current COVID-19 pandemic. Early diagnosis of viral... (Review)
Review
The proliferation and transmission of viruses has become a threat to worldwide biosecurity, as exemplified by the current COVID-19 pandemic. Early diagnosis of viral infection and disease control have always been critical. Virus detection can be achieved based on various plasmonic phenomena, including propagating surface plasmon resonance (SPR), localized SPR, surface-enhanced Raman scattering, surface-enhanced fluorescence and surface-enhanced infrared absorption spectroscopy. The present review covers all available information on plasmonic-based virus detection, and collected data on these sensors based on several parameters. These data will assist the audience in advancing research and development of a new generation of versatile virus biosensors.
Topics: COVID-19; Humans; Nanostructures; Pandemics; SARS-CoV-2; Spectrometry, Fluorescence; Spectrophotometry, Infrared; Spectrum Analysis, Raman; Surface Plasmon Resonance
PubMed: 33452375
DOI: 10.1038/s42003-020-01615-8 -
Journal of Nanobiotechnology Dec 2022Surface-enhanced Raman scattering (SERS) is a very promising tool for the direct detection of biomarkers for the diagnosis of i.e., cancer and pathogens. Yet, current... (Review)
Review
Surface-enhanced Raman scattering (SERS) is a very promising tool for the direct detection of biomarkers for the diagnosis of i.e., cancer and pathogens. Yet, current SERS strategies are hampered by non-specific interactions with co-existing substances in the biological matrices and the difficulties of obtaining molecular fingerprint information from the complex vibrational spectrum. Raman signal enhancement is necessary, along with convenient surface modification and machine-based learning to address the former issues. This review aims to describe recent advances and prospects in SERS-based approaches for cancer and pathogens diagnosis. First, direct SERS strategies for key biomarker sensing, including the use of substrates such as plasmonic, semiconductor structures, and 3D order nanostructures for signal enhancement will be discussed. Secondly, we will illustrate recent advances for indirect diagnosis using active nanomaterials, Raman reporters, and specific capture elements as SERS tags. Thirdly, critical challenges for translating the potential of the SERS sensing techniques into clinical applications via machine learning and portable instrumentation will be described. The unique nature and integrated sensing capabilities of SERS provide great promise for early cancer diagnosis or fast pathogens detection, reducing sanitary costs but most importantly allowing disease prevention and decreasing mortality rates.
Topics: Spectrum Analysis, Raman; Nanostructures
PubMed: 36544151
DOI: 10.1186/s12951-022-01711-3 -
Journal of Natural Products Dec 2019Serlyticin-A is a secondary metabolite first isolated from a culture of grown using squid pen as the sole carbon/nitrogen source. A previous study by Kuo et al....
Serlyticin-A is a secondary metabolite first isolated from a culture of grown using squid pen as the sole carbon/nitrogen source. A previous study by Kuo et al. demonstrated that it has antioxidative and antiproliferative properties. However, the proposed chemical structure of serlyticin-A is likely incorrect based on the thermodynamic instability of its three contiguous heteroatom-heteroatom bonds. Here, we use quantum chemical calculations to predict H and C chemical shifts for serlyticin-A and demonstrate a discrepancy between the calculated and experimental chemical shifts. We then propose several reasonable alternative structures for serlyticin-A. Considering the known antioxidant and antiproliferative activity of hydroxamic acids as well as their stability and prevalence in natural products of bacterial origin, we believe that serlyticin-A is most likely 3-indolylacetohydroxamic acid (). We provide our rationale for this assignment as well as experimental data for pure 3-indolylacetohydroxamic acid obtained via de novo synthesis. This study highlights the power of computational NMR shift prediction to revise chemical structures for natural products like serlyticin-A.
Topics: Molecular Structure; Quantum Theory; Serratia; Spectrum Analysis
PubMed: 31840986
DOI: 10.1021/acs.jnatprod.9b00859 -
Journal of Pharmaceutical and... Apr 2021Falsified medicines affect public health all around the globe. Complex distribution routes, illegal online webshops and reuse of packaging materials make them hard to... (Review)
Review
Falsified medicines affect public health all around the globe. Complex distribution routes, illegal online webshops and reuse of packaging materials make them hard to detect. In order to tackle this problem, detection methods for the recognition of suspicious medicines and subsequent confirmation of falsification by analytical techniques is required. In this review, we focus on the developments and challenges that existed in the last five years (2015-2020) in the detection and analysis of falsified medicines. These challenges might have not been solved yet or arisen with new types of falsifications, new analytical techniques or detection strategies. Detection of suspicious medicines starts with visual inspection of packaging materials. However, re-use of packaging materials and high-quality imitations complicate visual inspection. Recent developments in the analysis of packaging by microscopic and spectroscopic techniques such as optical microscopy, X-ray fluorescence, infrared spectroscopy and Raman spectroscopy or microscopy, in combination with multivariate analysis show promising results in the detection of falsified medicines. An ongoing big challenge in the analysis of falsified medicines is the affordability of analytical devices. Yet, recent reports showed that lower cost devices, such as Counterfeit Drug Indicator or Counterfeit Detection device version 3 show promising use in the detection of falsified medicines. Furthermore, combining the outcomes of different low-cost analytical techniques, such as Minilab, colorimetry and Counterfeit Drug Indicator significantly increased selectivity and sensitivity in the detection of falsified medicines. Also, recent developments make it possible to link a low-cost technique, such as TLC, to mobile phones. Proper training of personnel has shown room for improvement and remains a challenge, even for relatively simple techniques. With an increased use of analytical fingerprints, an upcoming challenge is the accessibility of the growing pool of data. There is also the need of validated reference libraries on both national and international levels. Developments of the last few years bring us a step closer in the fight against falsified medicines, however challenges remain in the worldwide accessibility of affordable, easily operable and sensitive techniques.
Topics: Counterfeit Drugs; Drug Packaging; Spectrophotometry, Infrared; Spectrum Analysis, Raman
PubMed: 33582458
DOI: 10.1016/j.jpba.2021.113948 -
Molecules (Basel, Switzerland) Nov 2022Imidazole derivatives have found wide application in organic and medicinal chemistry. In particular, benzimidazoles have proven biological activity as antiviral,...
Imidazole derivatives have found wide application in organic and medicinal chemistry. In particular, benzimidazoles have proven biological activity as antiviral, antimicrobial, and antitumor agents. In this work, we experimentally and theoretically investigated N-Butyl-1H-benzimidazole. It has been shown that the presence of a butyl substituent in the N position does not significantly affect the conjugation and structural organization of benzimidazole. The optimized molecular parameters were performed by the DFT/B3LYP method with 6-311++G(d,p) basis set. This level of theory shows excellent concurrence with the experimental data. The non-covalent interactions that existed within our compound N-Butyl-1H-benzimidazole were also analyzed by the AIM, RDG, ELF, and LOL topological methods. The color shades of the ELF and LOL maps confirm the presence of bonding and non-bonding electrons in N-Butyl-1H-benzimidazole. From DFT calculations, various methods such as molecular electrostatic potential (MEP), Fukui functions, Mulliken atomic charges, and frontier molecular orbital (HOMO-LUMO) were characterized. Furthermore, UV-Vis absorption and natural bond orbital (NBO) analysis were calculated. It is shown that the experimental and theoretical spectra of N-Butyl-1H-benzimidazole have a peak at 248 nm; in addition, the experimental spectrum has a peak near 295 nm. The NBO method shows that the delocalization of the aσ-electron from σ (C1-C2) is distributed into antibonding σ* (C1-C6), σ* (C1-N26), and σ* (C6-H11), which leads to stabilization energies of 4.63, 0.86, and 2.42 KJ/mol, respectively. Spectroscopic investigations of N-Butyl-1H-benzimidazole were carried out experimentally and theoretically to find FTIR vibrational spectra.
Topics: Quantum Theory; Spectroscopy, Fourier Transform Infrared; Spectrum Analysis, Raman; Models, Molecular; Benzimidazoles
PubMed: 36431965
DOI: 10.3390/molecules27227864 -
Molecules (Basel, Switzerland) Jul 2022The rational design of small building block molecules and understanding their molecular assemblies are of fundamental importance in creating new stimuli-responsive...
The rational design of small building block molecules and understanding their molecular assemblies are of fundamental importance in creating new stimuli-responsive organic architectures with desired shapes and functions. Based on the experimental results of light-induced conformational changes of four types of triangular azo dyes with different terminal functional groups, as well as absorption and fluorescence characteristics associated with their molecular assemblies, we report that aggregation-active emission enhancement (AIEE)-active compound () substituted with sterically crowded -butyl (-Bu) groups showed approximately 35% light-induced molecular switching and had a strong tendency to assemble into highly stable hexagonal structures with AIEE characteristics. Their sizes were regulated from nanometer-scale hexagonal rods to micrometer-scale sticks depending on the concentration. This is in contrast to other triangular compounds with bromo (Br) and triphenylamine (TPA) substituents, which exhibited no photoisomerization and tended to form flexible fibrous structures. Moreover, non-contact exposure of the fluorescent hexagonal nanorods to ultraviolet (UV) light led to a dramatic hexagonal-to-amorphous structure transition. The resulting remarkable variations, such as in the contrast of microscopic images and fluorescence characteristics, were confirmed by various microscopic and spectroscopic measurements.
Topics: Azo Compounds; Fluorescent Dyes; Spectrum Analysis
PubMed: 35889253
DOI: 10.3390/molecules27144380 -
Journal of Chromatography. A Apr 2021Mass spectrometry is now in widespread use for the detection of the analytes separated by chromatography. Electron ionization is the most frequently used method in mass... (Review)
Review
Mass spectrometry is now in widespread use for the detection of the analytes separated by chromatography. Electron ionization is the most frequently used method in mass spectrometry. However, this ionization technique sometimes suffers from extensive fragmentation of analytes, which makes identification difficult. A photoionization technique has been developed for suppressing this fragmentation and for subsequently observing a molecular ion. A variety of lasers have been employed for the sensitive and selective ionization of organic compounds. A femtosecond laser has a high peak power and is preferential for efficient ionization as well as for suppressing fragmentation, providing valuable information concerning molecular weight and chemical structure as well. In this review, we report on applications of femtosecond ionization mass spectrometry combined with gas chromatography.
Topics: Chromatography; Gas Chromatography-Mass Spectrometry; Mass Spectrometry; Polycyclic Aromatic Hydrocarbons; Spectrum Analysis, Raman; Thermodynamics
PubMed: 33714081
DOI: 10.1016/j.chroma.2021.462023 -
International Journal of Molecular... Dec 2022The paper compares the experimental FT-IR, UV-vis, and H NMR spectra of isoconazole and bifonazole with the density functional theory (DFT) calculations using different...
The paper compares the experimental FT-IR, UV-vis, and H NMR spectra of isoconazole and bifonazole with the density functional theory (DFT) calculations using different functionals. The results were compared with previously reported data related to their analogue, posaconazole. The analysis of calculated IR spectra with use of CAM-B3LYP (isoconazole) or B3LYP (bifonazole) functionals shows good accordance with the experimental IR spectrum. The best compatibility between the experimental and theoretical UV spectra was observed with the use of B3LYP or wB97XD functionals for isoconazole or bifonazole, respectively. The reason for the difference in the UV-vis spectra of isoconazole and bifonazole was discussed based on linear response time-dependent DFT and natural bond orbital methods. The calculated H NMR spectrum shows that the DFT formalism, particularly the B3LYP functional, give an accurate description of the isoconazole and bifonazole chemical shifts.
Topics: Models, Molecular; Spectroscopy, Fourier Transform Infrared; Spectrum Analysis, Raman; Spectrophotometry, Ultraviolet; Quantum Theory; Thermodynamics; Vibration
PubMed: 36613962
DOI: 10.3390/ijms24010520 -
International Journal of Molecular... Nov 2023Surface-enhanced Raman scattering (SERS) is of growing interest for a wide range of applications, especially for biomedical analysis, thanks to its sensitivity,... (Review)
Review
Surface-enhanced Raman scattering (SERS) is of growing interest for a wide range of applications, especially for biomedical analysis, thanks to its sensitivity, specificity, and multiplexing capabilities. A crucial role for successful applications of SERS is played by the development of reproducible, efficient, and facile procedures for the fabrication of metal nanostructures (SERS substrates). Even more challenging is to extend the fabrication techniques of plasmonic nano-textures to atomic force microscope (AFM) probes to carry out tip-enhanced Raman spectroscopy (TERS) experiments, in which spatial resolution below the diffraction limit is added to the peculiarities of SERS. In this short review, we describe recent studies performed by our group during the last ten years in which novel nanofabrication techniques have been successfully applied to SERS and TERS experiments for studying bio-systems and molecular species of environmental interest.
Topics: Spectrum Analysis, Raman; Nanostructures; Metals
PubMed: 38003354
DOI: 10.3390/ijms242216164 -
Journal of the American Society For... Dec 2020Imaging mass spectrometry has become a mature molecular mapping technology that is used for molecular discovery in many medical and biological systems. While powerful by... (Review)
Review
Imaging mass spectrometry has become a mature molecular mapping technology that is used for molecular discovery in many medical and biological systems. While powerful by itself, imaging mass spectrometry can be complemented by the addition of other orthogonal, chemically informative imaging technologies to maximize the information gained from a single experiment and enable deeper understanding of biological processes. Within this review, we describe MALDI, SIMS, and DESI imaging mass spectrometric technologies and how these have been integrated with other analytical modalities such as microscopy, transcriptomics, spectroscopy, and electrochemistry in a field termed multimodal imaging. We explore the future of this field and discuss forthcoming developments that will bring new insights to help unravel the molecular complexities of biological systems, from single cells to functional tissue structures and organs.
Topics: Animals; Electrochemical Techniques; Gene Expression Profiling; Humans; Mass Spectrometry; Microscopy; Multimodal Imaging; Spectrophotometry, Infrared; Spectrum Analysis, Raman; Transcriptome
PubMed: 32886506
DOI: 10.1021/jasms.0c00232