Search

This paper examines the distribution and chemical properties of beached plastic pellets along the Ionian and Tyrrhenian coasts of Southern Italy. Three locations have been sampled: Agnone Bagni (SR) and Paradiso (ME) on the Ionian coast of Sicily, Baia del Tono in Milazzo (ME) on the Sicilian Tyrrhenian coast, and Pizzo Calabro (VV) in Calabria on the Tyrrhenian coast. Variations in shape, size, compactness, color, and other physical features, correlated with residence times and transport, has been highlighted. Raman spectroscopy, used in a portable configuration, enabled rapid identification of polymer types, demonstrating its utility for on-site plastic pollutant monitoring. Polyethylene and polypropylene were the predominant polymers. Principal component analysis of the spectra determined the optimal chemometric classification of pellets by composition, avoiding interference or distortion. In conclusion, the study provided preliminary insights into pellet abundance, composition, weathering extent, and distribution across these shorelines, underscoring the importance of regular beach monitoring., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Trusted methods for identifying different Multiple Myeloma (MM) cells and their biological diversity due to their immunophenotypic variety are often little detailed and difficult to find in literature. In this work, we show that micro-Raman spectroscopy can be used to highlight if there is a certain degree of distinction or correlation between the MM subtype plasmacells in relation to the cluster of differentiation (CD45+/CD38+/CD138-) and (CD45-/CD38+/CD138+). After taking samples from the bone marrow of patients with Multiple Myeloma, the PCs were sorted by flow cytometry, selecting the most common CD of the disease, i.e. CD 45, CD38 and CD138. Some spectral differences are observed comparing the Raman spectra of the two set of samples investigated. To better define in which spectral regions there are greater differences and, therefore, to which biological contributions the changes refers, we also explored the principal component analysis (PCA) of the collected Raman data. The spectral variations between the different sorted cells have been highlighted by plotting loading vectors PC1 and PC2, which shows a net differentiation between the two set of cells. Ultimately, the differences shown by PCA have been associated with the spectral variations observed and explained in terms of changes of proteins and lipid contributions. Thus, the differentiation of Multiple Myeloma subtype plasma cells by confocal micro-Raman spectroscopy can be proposed as a diagnostic tool in the speeding up of cell identification, assessing the intracellular biochemical changes that take place in cancer cells., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021. Published by Elsevier B.V.)

Sepsis is a systemic inflammatory response ensuing from presence and persistence of microorganisms in the bloodstream. The possibility to identify them at low concentrations may improve the problem of human health and therapeutic outcomes. So, sensitive and rapid diagnostic systems are essential to evaluate bacterial infections during the time, also reducing the cost. In this study, from random M13 phage display libraries, we selected phage clones that specifically bind surface of Staphyloccocus aureus, Pseudomonas aeruginosa and Escherichia coli. Then, commercial magnetic beads were functionalized with phage clones through covalent bond and used as capture and concentrating of pathogens from blood. We found that phage-magnetic beads complex represents a network which enables a cheap, high sensitive and specific detection of the bacteria involved in sepsis by micro-Raman spectroscopy. The enter process required 6 h and has the limit of detection of 10 Colony Forming Units on 7 ml of blood (CFU/7 ml)., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Surface-enhanced Raman spectroscopy has emerged as a widely used tool in the identification of organic dyes in works of art. Indigo is among the most used organic pigment, its identification can therefore give important information about the provenience and the making of the investigated work of art. In this work, we combine Surface Enhanced Raman Spectroscopy (SERS) experiments with density functional theory (DFT) computations of the Raman frequencies of indigo and an indigo molecule adsorbed onto a silver surface made of 16 silver atoms. The SERS spectrum of a molecule adsorbed on a metallic surface, in fact, can differ from the corresponding Raman one. The knowledge and the comprehension of the SERS spectrum then are mandatory in dyes identification. Experimental SERS spectra were acquired using ad hoc SERS active substrates consisting of pulsed laser ablated silver nanoparticles deposited onto a polishing sheet. The polishing sheet surface roughness is able to remove some pigments grains from the surface of a work of art without damage. DFT calculations provide a good description of the observed SERS spectra, in particular, the indigo-Ag 16 structure gives a better description with respect to structures where only one or two silver atoms attached to the indigo molecule are considered., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Current methods for identifying neoplastic cells and discerning them from their normal counterparts are often nonspecific and biologically perturbing. Here, we show that single-cell micro-Raman spectroscopy can be used to discriminate between resistant and sensitive multiple myeloma cell lines based on their highly reproducible biomolecular spectral signatures. In order to demonstrate robustness of the proposed approach, we used two different cell lines of multiple myeloma, namely MM.1S and U266B1, and their counterparts MM.1R and U266/BTZ-R subtypes, resistant to dexamethasone and bortezomib, respectively. Then, micro-Raman spectroscopy provides an easily accurate and noninvasive method for cancer detection for both research and clinical environments. Characteristic peaks, mostly due to different DNA/RNA ratio, nucleic acids, lipids and protein concentrations, allow for discerning the sensitive and resistant subtypes. We also explored principal component analysis (PCA) for resistant cell identification and classification. Sensitive and resistant cells form distinct clusters that can be defined using just two principal components. The identification of drug-resistant cells by confocal micro-Raman spectroscopy is thus proposed as a clinical tool to assess the development of resistance to glucocorticoids and proteasome inhibitors in myeloma cells., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Recently it has been shown that micro-Raman spectroscopy combined with multivariate analysis is able to discriminate among different types of tissues and tumoral cells by the detection of significant alterations and/or reorganizations of complex biological molecules, such as nucleic acids, lipids and proteins. Moreover, its use, being in principle a non-invasive technique, appears an interesting clinical tool for the evaluation of the therapeutical effects and of the disease progression. In this work we analyzed molecular changes in aged cultures of leukemia model U937 cells with respect to fresh cultures of the same cell line. In fact, structural variations of individual neoplastic cells on aging may lead to a heterogeneous data set, therefore falsifying confidence intervals, increasing error levels of analysis and consequently limiting the use of Raman spectroscopy analysis. We found that the observed morphological changes of U937 cells corresponded to well defined modifications of the Raman contributions in selected spectral regions, where markers of specific functional groups, useful to characterize the cell state, are present. A detailed subcellular analysis showed a change in cellular organization as a function of time, and correlated to a significant increase of apoptosis levels. Besides the aforementioned study, Raman spectra were used as input for principal component analysis (PCA) in order to detect and classify spectral changes among U937 cells., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Pseudo-first-order rate constants for the hydrolysis of acetylsalicylic acid as a function of temperature have been obtained by variable-temperature kinetic experiments. A method, based on a generalization of non-isothermal analysis, has been used that takes advantage of the capabilities of modern data collection and processing systems. Both spectrophotometric and, for the first time under non-isothermal conditions, fluorometric measurements have been carried out. The results obtained are identical to those obtained under the same conditions but using traditional constant-temperature kinetic runs. This provides the possibility of reducing the amounts of time and chemicals usually spent in collecting kinetic data in mechanistic studies in solution by an order of magnitude.