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Mikrochimica Acta Nov 2023The global environmental concern surrounding microplastic (MP) pollution has raised alarms due to its potential health risks to animals, plants, and humans. Because of... (Review)
Review
The global environmental concern surrounding microplastic (MP) pollution has raised alarms due to its potential health risks to animals, plants, and humans. Because of the complex structure and composition of microplastics (MPs), the detection methods are limited, resulting in restricted detection accuracy. Surface enhancement of Raman spectroscopy (SERS), a spectral technique, offers several advantages, such as high resolution and low detection limit. It has the potential to be extensively employed for sensitive detection and high-resolution imaging of microplastics. We have summarized the research conducted in recent years on the detection of microplastics using Raman and SERS. Here, we have reviewed qualitative and quantitative analyses of microplastics and their derivatives, as well as the latest progress, challenges, and potential applications.
Topics: Animals; Humans; Spectrum Analysis, Raman; Microplastics; Plastics; Environmental Monitoring; Environmental Pollution
PubMed: 37953347
DOI: 10.1007/s00604-023-06044-y -
Nature Apr 2024Quantitative detection of various molecules at very low concentrations in complex mixtures has been the main objective in many fields of science and engineering, from...
Quantitative detection of various molecules at very low concentrations in complex mixtures has been the main objective in many fields of science and engineering, from the detection of cancer-causing mutagens and early disease markers to environmental pollutants and bioterror agents. Moreover, technologies that can detect these analytes without external labels or modifications are extremely valuable and often preferred. In this regard, surface-enhanced Raman spectroscopy can detect molecular species in complex mixtures on the basis only of their intrinsic and unique vibrational signatures. However, the development of surface-enhanced Raman spectroscopy for this purpose has been challenging so far because of uncontrollable signal heterogeneity and poor reproducibility at low analyte concentrations. Here, as a proof of concept, we show that, using digital (nano)colloid-enhanced Raman spectroscopy, reproducible quantification of a broad range of target molecules at very low concentrations can be routinely achieved with single-molecule counting, limited only by the Poisson noise of the measurement process. As metallic colloidal nanoparticles that enhance these vibrational signatures, including hydroxylamine-reduced-silver colloids, can be fabricated at large scale under routine conditions, we anticipate that digital (nano)colloid-enhanced Raman spectroscopy will become the technology of choice for the reliable and ultrasensitive detection of various analytes, including those of great importance for human health.
Topics: Colloids; Hydroxylamine; Metal Nanoparticles; Poisson Distribution; Proof of Concept Study; Reproducibility of Results; Silver; Single Molecule Imaging; Spectrum Analysis, Raman; Vibration
PubMed: 38632399
DOI: 10.1038/s41586-024-07218-1 -
Progress in Biophysics and Molecular... Sep 2023Amyloidosis is a deleterious condition caused by abnormal amyloid fibril build-up in living tissues. To date, 42 proteins that are linked to amyloid fibrils have been... (Review)
Review
Amyloidosis is a deleterious condition caused by abnormal amyloid fibril build-up in living tissues. To date, 42 proteins that are linked to amyloid fibrils have been discovered. Amyloid fibril structure variation can affect the severity, progression rate, or clinical symptoms of amyloidosis. Since amyloid fibril build-up is the primary pathological basis for various neurodegenerative illnesses, characterization of these deadly proteins, particularly utilising optical techniques have been a focus. Spectroscopy techniques provide significant non-invasive platforms for the investigation of the structure and conformation of amyloid fibrils, offering a wide spectrum of analyses ranging from nanometric to micrometric size scales. Even though this area of study has been intensively explored, there still remain aspects of amyloid fibrillization that are not fully known, a matter hindering progress in treating and curing amyloidosis. This review aims to provide recent updates and comprehensive information on optical techniques for metabolic and proteomic characterization of β-pleated amyloid fibrils found in human tissue with thorough literature analysis of publications. Raman spectroscopy and SAXS are well established experimental methods for study of structural properties of biomaterials. With suitable models, they offer extended information for valid proteomic analysis under physiologically relevant conditions. This review points to evidence that despite limitations, these techniques are able to provide for the necessary output and proteomics indication in order to extrapolate the aetiology of amyloid fibrils for reliable diagnostic purposes. Our metabolic database may also contribute to elucidating the nature and function of the amyloid proteome in development and clearance of amyloid diseases.
Topics: Humans; Amyloid; Amyloid beta-Peptides; Spectrum Analysis, Raman; Scattering, Small Angle; X-Ray Diffraction; Proteomics; Amyloidosis
PubMed: 37307955
DOI: 10.1016/j.pbiomolbio.2023.06.002 -
PloS One 2024In this study, a total of 30 elements (essential and non-essential or toxic) were determined in 25 foods consumed in Italy by children aged 0-6 months and produced in...
In this study, a total of 30 elements (essential and non-essential or toxic) were determined in 25 foods consumed in Italy by children aged 0-6 months and produced in Europe. Inductively Coupled Plasma-Atomic Emission Spectrometry and Inductively Coupled Plasma-Mass Spectrometry were used as measurement techniques for the elements of interest. The estimated intakes for one-year-old infants were compared with risk estimators and nutritional requirements. Data indicate that commercially available baby food in Italy provides an excellent contribution for Mn, Cu, Fe, Zn, Ca, K, and P, covering up to approximately 70% of the adequate intake (AI) for an infant aged 6-12 months. The intake of detectable toxic elements was always below the safety limit: even the most concentrated toxic elements never exceeded about 86% of the Provisional Tolerable Weekly Intake (PTWI). This result indicates that the analyzed baby food is of good quality and does not pose risks to children's health.
Topics: Infant; Child; Humans; Infant Food; Spectrum Analysis; Nutritional Requirements; Italy; Europe
PubMed: 38386635
DOI: 10.1371/journal.pone.0297158 -
Nature Protocols Sep 2023The interactions between molecules and noble metal nanosurfaces play a central role in many areas of nanotechnology. The surface chemistry of noble metal surfaces under... (Review)
Review
The interactions between molecules and noble metal nanosurfaces play a central role in many areas of nanotechnology. The surface chemistry of noble metal surfaces under ideal, clean conditions has been extensively studied; however, clean conditions are seldom met in real-world applications. We developed a sensitive and robust characterization technique for probing the surface chemistry of nanomaterials in the complex environments that are directly relevant to their applications. Surface-enhanced Raman spectroscopy (SERS) can be used to probe the interaction of plasmonic nanoparticles with light to enhance the Raman signals of molecules near the surface of nanoparticles. Here, we explain how to couple SERS with surface-accessible plasmonic-enhancing substrates, which are capped with weakly adsorbing capping ligands such as citrate and chloride ions, to allow molecule-metal interactions to be probed in situ and in real time, thus providing information on the surface orientation and the formation and breaking of chemical bonds. The procedure covers the synthesis and characterization of surface-accessible colloids, the preliminary SERS screening with agglomerated colloids, the synthesis and characterization of interfacial nanoparticle assemblies, termed metal liquid-like films, and the in situ biphasic SERS analysis with metal liquid-like films. The applications of the approach are illustrated using two examples: the probing of π-metal interactions and that of target/ligand-particle interactions on hollow bimetallic nanostars. This protocol, from the initial synthesis of the surface-accessible plasmonic nanoparticles to the final in situ biphasic SERS analysis, requires ~14 h and is ideally suited to users with basic knowledge in performing Raman spectroscopy and wet synthesis of metal nanoparticles.
Topics: Gold; Spectrum Analysis, Raman; Colloids; Nanotechnology; Metal Nanoparticles
PubMed: 37495750
DOI: 10.1038/s41596-023-00851-6 -
Mikrochimica Acta Dec 2023The aim of this study is to develop a simple but rapid method for the determination of foodborne pathogens in complex matrices (beverages) by surface enhanced Raman...
The aim of this study is to develop a simple but rapid method for the determination of foodborne pathogens in complex matrices (beverages) by surface enhanced Raman spectroscopy (SERS) combined with Au nanostar solid-phase substrates. The star-shaped singlet Au nanostructure was formed on the surface of a stainless steel sheet by chemical replacement reaction. Rhodamine 6G verified the sensitivity and reproducibility of this substrate, and the relative standard deviations of the SERS intensity at 1312 cm, 1364 cm, and 1510 cm displacements were 3.40%, 5.64%, and 3.48%, respectively. By detecting four pathogens in beverage samples on Au nanostar substrates, the utility of the SERS assay was demonstrated, while the combination of principal component analysis (PCA) and hierarchical cluster analysis (HCA) further enabled the isolation and identification of pathogens. The results of spiked beverages were validated in conventional culture identification and Vitek 2 Compact biochemical identification system experiments. Thus, this research demonstrated that Au nanostar substrates can be effectively utilized for the recognition of pathogenic bacteria and have immense promise to advance the progress of quick detection of foodborne pathogens and food safety.
Topics: Metal Nanoparticles; Reproducibility of Results; Gold; Spectrum Analysis, Raman; Beverages
PubMed: 38093122
DOI: 10.1007/s00604-023-06105-2 -
Microscopy and Microanalysis : the... Jul 2023
Topics: Spectrum Analysis
PubMed: 37613310
DOI: 10.1093/micmic/ozad067.268 -
Spectrochimica Acta. Part A, Molecular... Oct 2023Monoclonal antibodies provide highly specific and effective therapies for the treatment of chronic diseases. These protein-based therapeutics, or drug substances, are...
Monoclonal antibodies provide highly specific and effective therapies for the treatment of chronic diseases. These protein-based therapeutics, or drug substances, are transported in single used plastic packaging to fill finish sites. According to good manufacturing practice guidelines, each drug substance needs to be identified before manufacturing of the drug product. However, considering their complex structure, it is challenging to correctly identify therapeutic proteins in an efficient manner. Common analytical techniques for therapeutic protein identification are SDS-gel electrophoresis, enzyme linked immunosorbent assays, high performance liquid chromatography and mass spectrometry-based assays. Although effective in correctly identifying the protein therapeutic, most of these techniques need extensive sample preparation and removal of samples from their containers. This step not only risks contamination but the sample taken for the identification is destroyed and cannot be re-used. Moreover, these techniques are often time consuming, sometimes taking several days to process. Here, we address these challenges by developing a rapid and non-destructive identification technique for monoclonal antibody-based drug substances. Raman spectroscopy in combination with chemometrics were used to identify three monoclonal antibody drug substances. This study explored the impact of laser exposure, time out of refrigerator and multiple freeze thaw cycles on the stability of monoclonal antibodies. and demonstrated the potential of using Raman spectroscopy for the identification of protein-based drug substances in the biopharmaceutical industry.
Topics: Spectrum Analysis, Raman; Antibodies, Monoclonal; Mass Spectrometry; Chromatography, High Pressure Liquid
PubMed: 37209478
DOI: 10.1016/j.saa.2023.122872 -
Analytical Chemistry Sep 2023The purity of tandem mass spectrometry (MS/MS) is essential to MS/MS-based metabolite annotation and unknown exploration. This work presents a approach to cleaning...
The purity of tandem mass spectrometry (MS/MS) is essential to MS/MS-based metabolite annotation and unknown exploration. This work presents a approach to cleaning chimeric MS/MS spectra generated in liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based metabolomics. The assumption is that true fragments and their precursors are well correlated across the samples in a study, while false or contamination fragments are rather independent. Using data simulation, this work starts with an investigation of the negative effects of chimeric MS/MS spectra on spectral similarity analysis and molecular networking. Next, the characteristics of true and false fragments in chimeric MS/MS spectra were investigated using MS/MS of chemical standards. We recognized three fragment peak attributes indicative of whether a peak is a false fragment, including (1) intensity ratio fluctuation, (2) appearance rate, and (3) relative intensity. Using these attributes, we tested three machine learning models and identified XGBoost as the best model to achieve an area under the precision-recall curve of 0.98 for a clear separation between true and false fragments. Based on the trained model, we constructed an automated bioinformatic platform, DNMS2Purifier (short for de novo ), for metabolic features from metabolomics studies. DNMS2Purifier recognizes and processes chimeric MS/MS spectra without additional sample analysis or library confirmation. DNMS2Purifer was evaluated on a metabolomics data set generated with different MS/MS precursor isolation windows. It successfully captured the increase in the number of false fragments from the increased isolation window. DNMS2Purifier was also compared to MS2Purifier, an existing MS/MS spectral cleaning tool based on the addition of data-independent acquisition (DIA) analysis. Results indicated that DNMS2Purifier uniquely recognizes false fragments, which complements the previous DIA-based approach. Finally, DNMS2Purifier was demonstrated using a real experimental metabolomics study, showing improved MS/MS spectral quality and leading to an improved spectral match ratio and molecular networking outcome.
Topics: Tandem Mass Spectrometry; Chromatography, Liquid; Spectrum Analysis; Metabolomics; Computational Biology
PubMed: 37603462
DOI: 10.1021/acs.analchem.3c00736 -
Analytica Chimica Acta Jan 2024Infectious diseases caused by bacteria, viruses, fungi, and other pathogenic microorganisms are among the most harmful public health problems in the world, causing tens... (Review)
Review
Infectious diseases caused by bacteria, viruses, fungi, and other pathogenic microorganisms are among the most harmful public health problems in the world, causing tens of millions of deaths and incalculable economic losses every year. The establishment of rapid, simple, and highly sensitive diagnostic methods for pathogenic microorganisms is important for the prevention and control of infectious diseases, guidance of timely treatment, and the reduction of public safety risks. Lateral flow immunoassay (LFA) based on the colorimetric signal of colloidal gold is the most popular point-of-care testing technology at present, but it is limited by poor sensitivity and low throughput and hardly meets the needs of the highly sensitive screening of pathogenic microorganisms. In recent years, the combination of surface-enhanced Raman scattering (SERS) and LFA technology has developed into a novel analytical platform with high sensitivity and multiple detection capabilities and has shown great advantages in the detection of pathogenic microorganisms and infectious diseases. This review summarizes the working principle, design ideas, and application of the existing SERS-based LFA methods in pathogenic microorganism detection and further introduces the effect of new technologies such as Raman signal encoding, magnetic enrichment, novel membrane nanotags, and integrated Raman reading equipment on the performance of SERS-LFA. Finally, the main challenges and the future direction of development in this field of SERS-LFA are discussed.
Topics: Humans; Spectrum Analysis, Raman; Immunoassay; Communicable Diseases; Metal Nanoparticles
PubMed: 38049231
DOI: 10.1016/j.aca.2023.341931