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Multivariate calibration models often encounter challenges in extrapolating beyond the calibration instruments due to variations in hardware configurations, signal processing algorithms, or environmental conditions. Calibration transfer techniques have been developed to mitigate this issue. In this study, we introduce a novel methodology known as Supervised Factor Analysis Transfer (SFAT) aimed at achieving robust and interpretable calibration transfer. SFAT operates from a probabilistic framework and integrates response variables into its transfer process to effectively align data from the target instrument to that of the source instrument. Within the SFAT model, the data from the source instrument, the target instrument, and the response variables are collectively projected onto a shared set of latent variables. These latent variables serve as the conduit for information transfer between the three distinct domains, thereby facilitating effective spectra transfer. Moreover, SFAT explicitly models the noise variances associated with each variable, thereby minimizing the transfer of non-informative noise. Furthermore, we provide empirical evidence showcasing the efficacy of SFAT across three real-world datasets, demonstrating its superior performance in calibration transfer scenarios.

A new flow batch (FB) system for chemical vapor generation (CVG) is proposed for mercury (Hg) determination in fish. An inductively coupled plasma mass spectrometer was used as a detector. Low-cost peristaltic mini pumps were used to propel the solutions and different configurations of FB systems (reactor/gas/liquid separator) were studied. The proposed configuration of the FB-CVG system allows good sensitivity, low limit of detection (LOD) and low consumption of reagents and sample solutions. In summary, only 1 mL of reductant, 1 mL of acid and 0.16 mL of sample are needed. The proposed method has good linearity, precision (better than 5 %), LOD of 0.008 μg g^-1 and LOQ of 0.012 μg g^-1, and high sample throughput, allowing 90 measurements/h. The accuracy of the method was evaluated through the analysis of a certified reference material (DOLT-4 Dogfish Liver), whose result is in good agreement with certified value (t-test with 95 % confidence level) and the quantification limit meets current legislations, of 1.0 μg g^-1 (Brazil) and 0.3 μg g^-1 (EU). In addition, analyte recovery test was done, where Hg recovery was better than 95 %, demonstrating the good analytical performance of the method. To demonstrate the applicability of the method, five samples of fish tissue (muscle) were analyzed. The proposed FB-CVG system, in addition to being low cost, is robust and requires only the volume of reagents necessary for Hg vapor generation, producing a very low amount of waste. It can be concluded that the proposed system can be used for routine analysis for Hg determination in fish tissue. It is worth noting that with the appropriate adjustments, the system can be coupled to different Hg detectors.

Catechol, a polyphenolic molecule and significant organic chemical intermediate, is a highly dangerous environmental contaminant due to its unpredictable nature and potential harm to both humans and the environment. This study presents the development of Sn MOF@rGO-650, identified as a hollow cube by SEM and TEM, created by carbonizing rGO on the surface of Sn MOF after in situ encapsulation. The Sn MOF@rGO-650 modified glassy carbon electrode was successfully constructed for the electrochemical detection of catechol. Under optimal conditions, the sensor exhibited a detection limit of 33 nM, a linear range of 0.20 μM-28 μM, and good long-term stability and reproducibility. This work proves for the first time that Sn MOF@rGO-650 composites can effectively detect catechol in real environmental water samples, achieving recoveries between 95.7 % and 104.8 %, and is validated in UV spectroscopy, which highlights its potential for practical applications.

Enzyme catalytic cascade reactions based on peroxidase nanozymes and natural enzymes have aroused extensive attention in analytical fields. However, a majority of peroxidase nanozymes perform well only in acidic environments, resulting in their optimal pH mismatch with a neutral pH of natural enzymes, further restricting their application in biochemical sensing. Herein, Mn-doped CeO₂ (Mn/CeO₂) performing enhanced peroxidase-like activity at neutral conditions was prepared via a facile and feasible strategy. An effective enzyme cascade catalysis system via integrating glucose oxidase (GOx) with Mn/CeO₂ was developed for one-pot detection of glucose in serum at neutral conditions. Using one-pot multistep catalytic reactions, this work provided a detection platform that allows for faster detection and easier operations than traditional methods. Under optimized conditions, our assay performed a sensitive detection of glucose ranging from 2.0 μΜ to 300 μΜ and a low detection limit of 0.279 μΜ. Notably, favorable analytical outcomes for glucose detection in serum samples were obtained, exhibiting potential applications in clinical diagnosis.

A surface plasmon resonance imaging (SPRI)-based biosensor is demonstrated for the detection of both hydrogen peroxide (H₂O₂) and glucose. The H₂O₂ to be detected acts as an oxidant and etch the silver film. This process gradually effects on resonance condition and consequently the reflected light intensity at a fixed angle. The etching rate of the silver film shows a clear relation with the H₂O₂ concentration. Therefore, monitoring the reflected light intensity progressively changing over a few minutes, enables accurate detection of H₂O₂ concentrations ranging from 0 to 200 μM (within physiological range of 0.25-50 μM), with a remarkable limit of detection (LOD) as low as 40 nM. In this regard, the behavior of the surface plasmon resonance (SPR) dip in response to the reduction of the silver film thickness is predicted by Winspall simulation software. These simulation results are in good agreement with the experimental results. Moreover, the proposed method can be applied to determine glucose concentrations ranging from 0 to 10 mM, encompassing the physiological range of 3-8 mM. This is achieved by observing the generated H₂O₂ through the enzymatic oxidation reaction between glucose and glucose oxidase (Gox). The sensor demonstrates remarkable sensitivity and selectivity, with a detection limit as low as 175 μM for glucose concentration. Furthermore, accurate measurement of glucose concentration in an actual human serum sample is achievable with the proposed sensor, using the standard addition method. The suggested glucose sensor shows promising prospects for use in routine glucose testing, employing a label-free, real-time, and multiplex detection approach.© 2017 Elsevier Inc. All rights reserved.

Ginseng, a highly esteemed herbal medicine, has been utilized over 5000 years, predominantly in Far Eastern countries. Ginseng is categorized into garden ginseng (GG) and ginseng under forest (FG). However, in contrast to FG, excessive intake of GG may lead to potential adverse effects due to disruption of epithelial cell integrity, and the specific population groups that may be at higher risk. In this work, untargeted metabolomics were used to determine the heterogeneity between GG and FG, the data indicates that the content of Ethyl caffeate, Homoorientin, Citric acid and Quinic acid in GG were higher than in FG. Mass spectrometry imaging showed that ethyl caffeate and Homoorientin were concentrated on the brownish yellow exocarp of the primary root. Our experiments demonstrated that excessive exposure to ethyl caffeate and Homoorientin exacerbated the inflammatory response of HUVECs and reduced the expression of cell junctions. This suggest that the compounds causing adverse effects from excessive intake of GG are mainly concentrated in the yellow exocarp of the primary root of GG. These results suggest that untargeted metabolomics coupled with MALDI-MSI can visualize the spatial distribution of endogenous differential molecules of the same herb in different growth environments or developmental stages.

There is great interest in fabricating devices that can detect and remove water pollutants, especially heavy metal ions and dyes from wastewater, to promote sustainable water use. In this study, an extract of Borassus flabellifer leaves (BoF-LE) was used to synthesize silver nanoparticles (BoF-AgNPs), with the BoF-LE serving as a reducing and capping agent. The sensitivity and selectivity of BoF-AgNPs for Mn(II) ions were tested by comparing with the control sample and other competent metal ions. Our results showed that BoF-AgNPs are extremely sensitive and selective in detecting Mn(II) ions, with a detection limit of 0.3 ppb. HR-TEM, UV-Vis spectroscopy, and DLS investigations were used to confirm that BoF-AgNPs detect Mn(II) ions by an aggregation-based mechanism. Additionally, it was found that BoF-AgNPs are effective in rapidly decolorizing MB dye, as demonstrated by their ability to decolorize MB by 92.66% within 7 min. This study is the first to report successful synthesis of BoF-AgNPs and their two applications, which are enabled with an Inhibit-AND logic gate. Using BoF-AgNPs to detect and degrade water pollutants may promote sustainable water use.

Recently, peptide-drug conjugate (PDC) has become the most promising conjugated drug for tumor therapy after antibody-drug conjugate due to stronger tumor penetration capacity and lower immunogenicity. CBP-1018 was a PDC with dual-ligand conjugated to MMAE via a cleavable linker (MC-Val-Cit-PABC) that can be lysed by cathepsins B. In this study, two specific LC-MS/MS methods were developed and validated for the determination of CBP-1018 and its metabolite MMAE in human plasma. To prevent the cleavable MC-Val-Cit-PABC linker from degradation, a protease inhibitor (cOmplete solution) was added to the pre-cooled vacuum tubes and the separated plasma samples. The assays involved the pretreatment of CBP-1018 by protein precipitation with H₂O-ACN (1:9, v/v) and the extraction of MMAE by liquid-liquid extraction with ethyl acetate under alkaline condition to eliminate the interference of CBP-1018 on MMAE. The two analytes showed good linearities over the calibration ranges (R² ≥ 9980). Both accuracy and precision met the acceptance criteria. The validated methods were successfully applied to the phase I dose-escalation study of CBP-1018 injection in Chinese patients with solid tumors to evaluate the pharmacokinetic properties of CBP-1018 and MMAE. The results showed that CBP-1018 was eliminated immediately after injection and MMAE reached the maximum exposure at approximately 2 h after infusion. The maximum concentration of MMAE did not exceed 20.0 ng/mL, suggesting that the off-target toxicity of CBP-1018 injection was controllable.

Avian influenza viruses (AIV) are capable of infecting a considerable proportion of the world's population each year, leading to severe epidemics with high rates of morbidity and mortality. The methods now used to diagnose influenza virus A include the Western blot test (WB), hemagglutination inhibition (HI), and enzyme-linked immunosorbent assays (ELISAs). But because of their labor-intensiveness, lengthy procedures, need for costly equipment, and inexperienced staff, these approaches are considered inappropriate. The present review elucidates the recent advancements in the field of avian influenza detection through the utilization of nanomaterials-based immunosensors between 2014 and 2024. The classification of detection techniques has been taken into account to provide a comprehensive overview of the literature. The review encompasses a detailed illustration of the commonly employed detection mechanisms in immunosensors, namely, colorimetry, fluorescence assay, surface plasmon resonance (SPR), surface-enhanced Raman spectroscopy (SERS), electrochemical detection, quartz crystal microbalance (QCM) piezoelectric, and field-effect transistor (FET). Furthermore, the challenges and future prospects for the immunosensors have been deliberated upon. The present review aims to enhance the understanding of immunosensors-based sensing platforms for virus detection and to stimulate the development of novel immunosensors by providing novel ideas and inspirations. Therefore, the aim of this paper is to provide an updated information about biosensors, as a recent detection technique of influenza with its details regarding the various types of biosensors, which can be used for this review.

A fast and non-separative screening strategy is presented for the analysis of five urinary metabolites of polycyclic aromatic hydrocarbons (PAHs), namely 2-naphthol, 1-acenaphthenol, 2-hydroxyfluorene, 9-phenanthrol and 1-hydroxypyrene. These hydroxylated derivatives (OH-PAHs) were subjected to enzymatic hydrolysis and were extracted from urine using a liquid-liquid extraction (LLE). The profile signals were obtained by direct injection of the sample into a programmed temperature vaporizer coupled to a quadrupole mass spectrometer via a deactivated fused silica tubing (PTV-qMS). Semi-quantitative determination was carried out by means of partial least squares regression (PLS1) using urine samples free of the analytes and spiked at several uncorrelated concentration levels. The multivariate calibration models worked satisfactorily, with errors ranging between 30 and 33 % for all the analytes except for 1-acenaphthenol that provided an error of 39 % when external validation set was considered. The repeatability and reproducibility, expressed as relative standard deviation (RSD), were ranged between 8-16 % and 11-18 %, respectively. The proposed method could be a useful tool for semi-quantification purposes of five OH-PAHs in urine samples, identifying positive samples for subsequent further chromatographic separation (confirmation), thus saving time and costs.