Spectrochim Acta A Mol Biomol Spectrosc
July 2024
The advent of miniaturized NIR instruments, also known as compact, portable, or handheld, is revolutionizing how technology can be employed in forensics. In-field analysis becomes feasible and affordable with these new instruments, and a series of methods has been developed to provide the police and official agents with objective, easy-to-use, tailored, and accurate qualitative and quantitative forensic results. This work discusses the main aspects and presents a comprehensive and critical review of compact NIR spectrophotometers associated with analytical protocols to produce information on forensic matters.
View Article and Find Full Text PDFA comprehensive data set of ecstasy samples containing MDMA (N-methyl-3,4-methylenedioxyamphetamine) and MDA (3,4-methylenedioxyamphetamine) seized by the Brazilian Federal Police was characterized using spectral data obtained by a compact, low-cost, near-infrared Fourier-transform based spectrophotometer. Qualitative and quantitative characterization was accomplished using soft independent modeling of class analogy (SIMCA), linear discriminant analysis (LDA) classification, discriminating partial least square (PLS-DA), and regression models based on partial least square (PLS). By applying chemometric analysis, a protocol can be proposed for the in-field screening of seized ecstasy samples.
View Article and Find Full Text PDFNickel-metal hydride batteries (NiMH) are a secondary source of high aggregate value elements, such as nickel, manganese, cobalt, and rare earths, for which recycling typically involves acid lixiviation. Designing the recycling process requires accurate determination of the elements in the leachates, which is hindered by the high complexity of the matrix. In the present study, microwave-induced plasma atomic emission spectrometry (MIP-OES) was selected as the quantitative method for elemental analysis because of its environment friendliness and cost-effectiveness.
View Article and Find Full Text PDFIn a circular economy context, there is a growing need for more sustainable waste management options to recover elements from end-of-life materials. These "secondary ores" represent a source of critical elements that are often present in higher concentration compared to their primary ore. In this work, the recovery of lanthanum (La) from waste nickel metal hydride battery (NiMH) leachate is investigated using an aqueous biphasic system (ABS) process based on a pluronic triblock copolymer (L35).
View Article and Find Full Text PDFMost dengue virus (DENV) infections remain asymptomatic. This increases the risk of DENV transfusion transmission (TT-DENV) during outbreaks. We evaluated DENV viremia in 8475 blood donations assembled in minipools for the presence of DENV RNA.
View Article and Find Full Text PDFThe use of near-infrared spectroscopy (NIRS) based on a low-cost portable instrument for monitoring the quality of the three major formulations of ethanol-based hand sanitizers used for prevention against CoVID-19 disease is described. The quality of the sanitizers was evaluated using two approaches. In the first, a qualitative method was developed to identify gross non-conformities, using NIR spectral data compression by principal components analysis and projection of the spectrum of the tested sample in the principal component space delimited by samples of sanitizers prepared in the laboratory.
View Article and Find Full Text PDFAn optical sensor (OS) was synthesized by mixing 10,12-pentacosadiinoic acid (PDA) with a triblock copolymer for use in the detection/quantification of lidocaine (LD) in seized cocaine hydrochloride (seized CH) samples. In the presence of LD, the OS presented a chromatic transition from blue to red, while no chromatic transition was observed for other typical cocaine adulterants or cocaine hydrochloride. Isothermal titration calorimetry analysis revealed specific interactions between the PDA molecules of the OS and the LD molecules, with these interactions being enthalpically favorable (-1.
View Article and Find Full Text PDFThe quality of omega-3 supplements, commercialized at substantial high prices and supplied by several manufacturers, must be assessed. The existing reference methods to attest the quality of omega-3 supplements are based on chromatography, which requires expensive equipment, a cumbersome analytical protocol to determine the contents of the active components, and operates ex-situ. This work evaluates, comprehensively, the feasibility of a low-cost near-infrared spectrophotometer and simple chemometrics to achieve fast and robust characterization of omega-3 supplements.
View Article and Find Full Text PDFObjective: The objective of this study was to examine the Borrelia seroprevalence among blood donors in Southeast Brazil.
Background: There is evidence that Borrelia spirochetes are circulating in Brazil; however, there are no studies that characterise these bacteria and investigate their seroprevalence in the Brazilian population. Such a situation, combined with a recent outbreak of tick-borne Rocky Mountain spotted fever in the São Paulo state demonstrates the increasing role of ticks as arthropod vectors in Brazil.
Objectives: The objectives of this study were to evaluate the prevalence of Human Pegivirus-1 (HPgV-1) viremia and genotype diversity among healthy blood donors from the Eastern Brazilian Amazon (city of Macapá, State of Amapá). There is little information for prevalence and circulation of HPgV-1 in this remote Brazilian region.
Materials And Methods: We conducted a study evaluating the HPgV-1 RNA prevalence and circulating genotypes in 431 volunteer blood donors originating from the Eastern Brazilian Amazon.
The potential of a low-cost (∼US$ 1000) portable near-infrared (NIR) spectrophotometer for in situ characterization of seized cocaine samples was evaluated. A set of 240 samples of cocaine seized in several regions and cities across Brazil by its federal police was employed in this study. These samples were previously analyzed by chromatography at the Forensic Chemistry Laboratory of the National Institute of Criminalistics in Brasília-DF for the contents of several constituents to chemically characterize the samples.
View Article and Find Full Text PDFFe(II) and Fe(III) have distinct chemical and biological functions. Consequently, it is more important to determine the fraction of both oxidation state that knowing the total iron concentration in a sample. However, green methods for iron speciation are still limited.
View Article and Find Full Text PDFBovine serum albumin (BSA)/curcumin binding and dye photodegradation stability were evaluated. BSA/curcumin complex showed 1:1 stoichiometry, but the thermodynamic binding parameters depended on the technique used and BSA conformation. The binding constant was of the order of 10L·mol by fluorescence and microcalorimetric, and 10 and 10L·mol by surface plasmon resonance (steady-state equilibrium and kinetic experiments, respectively).
View Article and Find Full Text PDFPolydiacetylene (PDA) vesicles have been applied as optical sensors in different areas, although there are difficulties in controlling their responses. In this study, we prepared nanoblends of PDA with triblock copolymers (TC) as a better sensor system for detecting temperature change. The influences of diacetylene (DA) monomer, and the TC chemical structure and concentration on the colorimetric response (CR) were examined.
View Article and Find Full Text PDFBackground: In 2015, there was a large Zika virus (ZIKV) outbreak in Brazil. The proportion of asymptomatic infections is very high, and it is possible for transfusion-transmitted ZIKV (TT-ZIKV) infection to occur. The prevalence of asymptomatic ZIKV infection among Brazilian blood donors during this epidemic outbreak is unknown.
View Article and Find Full Text PDFCinnamic acid (CA) and methyl cinnamate (MC) have attracted interest of researchers because of their broad therapeutic functions. Here, we investigated the interaction of CA and MC with bovine serum albumin (BSA) at pH 3.5, 5.
View Article and Find Full Text PDFPrevious studies have demonstrated that some components of the leukocyte cell membrane, CR3 (Mac-1, CD11b/CD18) and p150/95, are able to bind to denatured proteins. Thus, it is of interest to know which effector functions of these cells can be triggered by these receptors when they interact with particles or surfaces covered with denatured proteins. In the present study we analyzed their possible role as mediators of phagocytosis of red cells covered with denatured bovine serum albumin (BSA) by mouse peritoneal macrophages.
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