Substances In Matrices Research Articles

Green Forensic Toxicology: Optimizing Chlordiazepoxide Detection in Milk, Whiskey, and Whiskey Cream Matrices

Forensic toxicology plays a crucial role in detecting and quantifying drugs, toxins, and poisons in biological and non-biological samples to aid criminal and legal investigations. However, traditional approaches often involve significant resource use and pose environmental concerns. This study focuses on the identification and quantification of chlordiazepoxide, a benzodiazepine commonly associated with drug-facilitated crimes, in milk, whiskey, and whiskey cream matrices using Thin Layer Chromatography (TLC) followed by confirmatory UV-Vis spectroscopy. The methodology involved spiking the matrices with chlordiazepoxide, employing liquid-liquid extraction (LLE) with chloroform and water, and conducting preliminary tests such as the Marquis Test and TLC. The chloroform (90:10) solvent system emerged as the most effective for optimal separation, with an average retention factor (Rf) of 0.42 ± 0.03. UV-Vis spectroscopy provided quantitative confirmation, revealing absorption peaks at 246 nm, 262 nm, and 308 nm. Recovery rates varied across matrices, with milk exhibiting lower recovery (88.5%) due to protein interactions, while whiskey and whiskey cream showed higher recoveries (91.7% and 93.2%, respectively) following repeated extraction cycles. The study demonstrates the reliability and cost-effectiveness of combining TLC and UV-Vis spectroscopy for detecting psychoactive substances in complex food and beverage matrices. The findings emphasize the importance of a multi-tiered analysis strategy, aligning with forensic best practices, and highlight the need for confirmatory analysis to ensure legal admissibility. The successful application of these methods reinforces their relevance in high-throughput laboratory settings and their potential to support forensic investigations involving drug-facilitated crimes.

Standard operating procedures for the determination of abuse substances in biological matrices

Standard operating procedures for the determination of abuse substances in biological matrices

Characterisation of the prdx4 gene in Squalius cephalus and its role in freshwater environments with varying impact of perfluoroalkyl substances (PFAS).

Characterisation of the prdx4 gene in Squalius cephalus and its role in freshwater environments with varying impact of perfluoroalkyl substances (PFAS).

Dual-Mode Colorimetric/SERS Lateral Flow Immunoassay with Machine Learning-Driven Optimization for Ultrasensitive Mycotoxin Detection.

Detecting and quantifying mycotoxins using LFIA are challenging due to the need for high sensitivity and accuracy. To address this, a dual-mode colorimetric-SERS LFIA was developed for detecting deoxynivalenol (DON). Rhodium nanocores provided strong plasmonic properties as the SERS substrate, while silver nanoparticles created electromagnetic "hotspots" to enhance signal sensitivity. Finite element modeling optimized the electromagnetic field intensity, and Prussian blue generated a distinct signal at 2156 cm-1, effectively reducing background interference. This dual-mode LFIA achieved a detection limit of 4.21 pg/mL, 37 times lower than that of colloidal gold-based LFIA (0.156 ng/mL). Machine learning algorithms, including ANN and KNN, enabled precise classification and quantification of contamination, achieving 98.8% classification accuracy and an MSE of 0.57. These results underscore the platform's potential for analyzing harmful substances in complex matrices and demonstrate the important role of machine learning-enhanced nanosensors in advancing detection technologies.

Comprehensive Evaluation of the Analytical Efficiency of Combustion Ion Chromatography for Per- and Polyfluoroalkyl Substances in Biological and Environmental Matrices.

Combustion ion chromatography (CIC) has emerged as a valuable tool for determining fluorine content attributable to per- and polyfluoroalkyl substances (PFAS) in biological and environmental samples. The total organofluorine (TOF) data from CIC complement information obtained by targeted analyses using liquid chromatography-tandem mass spectrometry (LC-MS/MS) because TOF includes PFAS that may not be captured by targeted techniques. However, the effect of different PFAS types (chain lengths, head groups, etc.) and matrices on combustion efficiency has not been systematically evaluated. Comparison of C4-C12 PFAS using equimolar quantities of fluorine (5.27 nmol F) demonstrated statistically equivalent CIC responses, indicating uniform combustion across chain lengths. Further, signals resulting from combustion times ranging from 7.5 to 15 min were statistically equivalent. However, fluorotelomer alcohols (FTOHs) exhibited losses due to volatility, requiring the use of an activated carbon sorbent to improve analytical signals. Matrix variations exhibited no change in PFAS combustion efficiency across chain lengths in water, blood, and biosolids. Total fluorine results from CIC analysis of real blood and biosolid samples were compared to targeted LC-MS/MS results. This study highlights the strengths and limitations of CIC as an important complement to targeted PFAS analysis and provide guidance for optimizing application-specific conditions and interpreting CIC results.

PASSIVE-SAMPLER EMPLOYED FOR ANTIFOULING BOOSTER BIOCIDES ANALYSES IN SEAWATER

The antifouling booster biocides are frequently studied for toxic effects on the aquatic ecosystems. The present investigation proposes passive silicone rubber samplers as a collection method for biocides, once these methods can concentrate substances in aqueous matrices at very low levels. Through the passive sampler-water partition coefficient (Ksw) and the analyte chemical nature, we can optimize their extraction from the membrane to apply in the sample medium. We used the co-solvent method to determine the Ksw of three third-generation antifouling biocides, chlorothalonil, dichlofluanid, and dichlorooctylisothiazolinone (DCOIT), with log Ksw = 2.24, 4.01, and 2.38, respectively. Improving extraction also led to a recovery range higher than 70%, determinations were carried out by gas chromatography with an electron capture detector. Biocides concentration in seawater samples from Itaqui port (São Marcos Bay, northern Brazil) ranged from 0.058 to 0.72 μg L-1 for chlorothalonil, 0.001 to 0.008 μg L-1 for dichlofluanid, and 0.018 to 0.64 μg L-1 for DCOIT.

A flexible and energy independent fluorescence radiation fiber film dosimeter fabricated by electrostatic spinning.

Doping fluorescent substances in polymer matrices has shown promising applications in radiation dose sensing. In this work, quinoline dye based polyvinyl chloride fibrous films with fiber diameters of 123 nm, 540 nm and 864 nm were obtained by electrostatic spinning. The introduction of the fiber film structure makes the fluorescent film dosimeter flexible and lightweight compared to normal solid fluorescent films and further extends the linear range of X-ray detection to 0-350 Gy. Furthermore, the dosimeter shows energy and dose rate independence, and the sensitivity of the dosimeter can be improved by the application of fiber films with thinner diameters. This flexible fiber membrane provides a candidate material for wearable visual dosimeters.

Cleaner cuts: Farmed fish and skin-off fillets are lower in per- and polyfluoroalkyl substances (PFAS).

Cleaner cuts: Farmed fish and skin-off fillets are lower in per- and polyfluoroalkyl substances (PFAS).

A SIFT Study of Reactions of Positive and Negative Ions With Polyfluoroalkyl (PFAS) Molecules in Dry and Humid Nitrogen at 393 K.

Data are required for SIFT-MS analysis of perfluoroalkyl and polyfluoroalkyl substances (PFAS), which are persistent in the environment and cause adverse health effects. Specifically, the rate coefficients and product ion branching ratios of the reactions of H3O+, NO+, O2 +•, O-•, OH-, O2 -•, NO2 - and NO3 - with PFAS vapours are needed. The dual polarity SIFT-MS instrument (Voice200) was used to generate these eight reagent ions and inject them into the flow tube with N2 carrier gas at a temperature of 393 K. Vapours of pentafluoropropionic acid, heptafluorobutyric acid, nonafluoro-1-hexanol, perfluoro-2-methyl-2-pentene, perfluorohexanoic acid, perfluoro(2-methyl-3-oxahexanoic) acid, tridecafluoro-1-octanol and nonafluorobutane-1-sulfonic acid were introduced in dry and humid air. Full-scan mass spectra were collected for all reagents at variable PFAS concentrations and analysed numerically. Rate coefficients were determined for 64 reactions, for which 55 positive and 71 negative product ions were identified. The branching ratios for the primary reaction channels were extracted from the data, and the secondary chemistry with H2O molecules was qualitatively assessed. The thermochemical data were calculated for the H3O+ reactions using density functional theory (DFT). An important observation is that secondary reactions with water molecules remove the positive product ions, making them unsuitable for practical SIFT-MS analysis of PFAS vapours. In contrast, most negative reaction product ions are not significantly affected by humidity and are thus preferred for the SIFT-MS analyses of PFAS substances in various gaseous matrices.

Mechanism of pyrazines and thioethers formation promoted by high oxygen concentration in the methionine-glucose Maillard reaction system.

The typical aroma compounds in methionine-glucose Maillard products often undergo further degradation and polymerization during storage and thermal processing, leading to flavor dispersion and aroma distortion. It is crucial to identify measures that enhance typical aroma substances in such flavor matrices. The effect of oxygen on the flavor formation of methionine-glucose thermal reaction system was explored by determining typical flavor substance contents and flavor differences. Compared with the oxygen concentration in the air (21%), a high oxygen concentration (30% and 40%) effectively promoted the formation of typical flavor substances. Pyrazines increased by 44% and thioethers increased by 13%. The reaction process and the content of key substances were both measured to explain the involvement of oxygen. It was found that high oxygen concentration increased the reaction efficiency of glucose and methionine and promoted the formation of α-dicarbonyl compounds, including glyoxal, methylglyoxal and 3-deoxyglucosinone. Moreover, a glyoxal-methylglyoxal-methionine model system was established to verify the effect of oxygen intervention on the formation of pyrazines and thioethers generating from α-dicarbonyl compounds. It was confirmed that a high oxygen concentration promoted the consumption of glyoxal and methylglyoxal, which were more readily converted into pyrazines and thioethers without forming melanoidins. A high concentration of oxygen promoted the formation of pyrazines and thioethers during the Maillard reaction of methionine and glucose, and effectively inhibited the occurrence of browning. The present study provides a new concept for the typical flavor enhancement of methionine-glucose Maillard reaction products. © 2024 Society of Chemical Industry.

Rapid Detection of Trace Levels of Perfluorooctanoic Acid Using Photothermal Cantilever Deflection Spectroscopy

Real-time detection of chemical contaminants in the environment using portable, low-cost sensors with high selectivity, sensitivity, reproducibility, and wide dynamic range is challenging because of the complex nature of analytes and sample matrices. The challenge is exacerbated when the targeted chemical contaminants appear at trace levels. There is currently an urgent need to develop chemical sensors that can selectively and sensitively detect emerging contaminants, such as per- and polyfluoroalkyl substances (PFAS) in various environmental matrices. We have developed a portable sensor system based on standoff detection. In this method, a surface containing perfluorooctanoic acid (PFOA) is irradiated with infrared radiation from a tunable source, and the scattered radiation is collected and detected with a bimatetial cantilever. The differential deflection of the cantilever as a function of irradiation wavelength shows the IR absorption spectrum of the PFOA. The experimental results show the detection of PFAS with high selectivity and with ppb sensitivity and the developed technique can detect the trace levels of contaminants in less than 5 min.

Enhanced industrial wastewater monitoring: method development for non-target screening of highly polar substances using ZIC-HILIC-HRMS

Non-target screening (NTS) plays a major role in the monitoring and management of water bodies. While the NTS of moderate to non-polar substances is well-established, the screening of highly polar chemicals remains challenging. In this study, a robust separation method for highly polar substances using zwitterionic hydrophilic interaction liquid chromatography coupled with high-resolution mass spectrometry (ZIC-HILIC-HRMS) was developed. This method was specifically designed for the NTS of industrial wastewater, with the objective of capturing a wide range of polar contaminants in each acquisition run. Method validation included assessing key parameters such as repeatability, reproducibility, linearity, and limit of detection (LOD). For repeatability and reproducibility, the average %RSD of intensity and retention time across all substances in different matrices—solvent, influent, and effluent—remained below 6% and 1%, respectively (n = 10). The method demonstrated good linearity (R2 > 0.99) for 75% of the substances, while LODs varied between 0.1 and 40 µg/L depending on the compound tested. The method was then applied for NTS analysis of untreated wastewater at various locations within a chemical industrial park. Additionally, the overall influent and effluent of an industrial wastewater treatment plant (WWTP) were monitored over a 10-day period. Principal component analysis (PCA) was performed to interpret the data, identifying irregularities in the wastewater content. Moreover, the method demonstrated the WWTP’s ability to achieve an average removal efficiency of approximately 90% for this category of substances in this period, while also detecting their degradation products in the effluent. Finally, the method was successfully integrated into the daily monitoring routine of the WWTP, ensuring continuous surveillance and improved management of wastewater treatment processes.Graphical abstract

Adsorbability of a wide range of per- and polyfluoroalkyl substances on granular activated carbon, ion exchange resin, and surface modified clay

Adsorbability of a wide range of per- and polyfluoroalkyl substances on granular activated carbon, ion exchange resin, and surface modified clay

Photodegradation of ciprofloxacin and its interaction with Cu(II) in different water matrices: Insight into degradation pathways

Photodegradation of ciprofloxacin and its interaction with Cu(II) in different water matrices: Insight into degradation pathways

Versatile Approaches of Quantum Dots in Biosensing and Imaging.

Cancer is considered a formidable global health threat, despite substantial strides in diagnosis, detection, and therapeutic strategies. Remarkable progress has been achieved in these realms, yet the survival rates for cancer patients have persisted at suboptimal levels over decades. Acknowledging the need to address the ongoing challenges in cancer survival rates, research efforts are being made to push the boundaries of innovation in diagnostic techniques, bioimaging, and drug delivery technologies. Over the past few years, nano(bio)technology-based approaches have been applied for biosensing and imaging applications to detect biochemical substances in various matrices. Among various nanoengineered particulates, quantum dots (QDs) have been recognized as versatile agents for these applications. QDs, often called artificial atoms, are characterized by the remarkable optical and electrical features which are essential for cytosensing, localized bioimaging and therapeutics. Here in this review, we have discussed various QDs as sensitive and selective agents for precise sensing and imaging of cancer cells. Both electrochemical and optical approaches have been used to describe the cytosensing detection methods. Furthermore, the bioimaging of malignant tumor cells and the drug delivery with therapeutic responses of QDs have also been highlighted. This review also lists the several kinds of QDs that are frequently used for such kinds of applications, such as carbon, graphene, zinc, and other types of hybrid-based QDs. Finally, to shed insight on prospective research, the advantages and potential of QDs are also highlighted. In this article, we also emphasize the limitations and address the difficulties associated with QDs in clinical applications in order to provide insights for potential solutions.

Current Challenges in Monitoring Low Contaminant Levels of Per- and Polyfluoroalkyl Substances in Water Matrices in the Field.

The Environmental Protection Agency (EPA) of the United States recently released the first-ever federal regulation on per- and polyfluoroalkyl substances (PFASs) for drinking water. While this represents an important landmark, it also brings about compliance challenges to the stakeholders in the drinking water industry as well as concerns to the general public. In this work, we address some of the most important challenges associated with measuring low concentrations of PFASs in drinking water in the field in real drinking water matrices. First, we review the "continuous monitoring for compliance" process laid out by the EPA and some of the associated hurdles. The process requires measuring, with some frequency, low concentrations (e.g., below 2 ppt or 2 ng/L) of targeted PFASs, in the presence of many other co-contaminants and in various conditions. Currently, this task can only (and it is expected to) be accomplished using specific protocols that rely on expensive, specialized, and laboratory-scale instrumentation, which adds time and increases cost. To potentially reduce the burden, portable, high-fidelity, low-cost, real-time PFAS sensors are desirable; however, the path to commercialization of some of the most promising technologies is confronted with many challenges, as well, and they are still at infant stages. Here, we provide insights related to those challenges based on results from ab initio and machine learning studies. These challenges are mainly due to the large amount and diversity of PFAS molecules and their multifunctional behaviors that depend strongly on the conditions of the media. The impetus of this work is to present relevant and timely insights to researchers and developers to accelerate the development of suitable PFAS monitoring systems. In addition, this work attempts to provide water system stakeholders, technicians, and even regulators guidelines to improve their strategies, which could ultimately translate in better services to the public.

Suspect screening of per-and polyfluoroalkyl substances in paper by selective and non-selective extraction with UHPLC-Q orbitrap MS

Suspect screening of per-and polyfluoroalkyl substances in paper by selective and non-selective extraction with UHPLC-Q orbitrap MS

Sensitive Detection of Genotoxic Substances in Complex Food Matrices by Multiparametric High-Content Analysis.

Genotoxic substances widely exist in the environment and the food supply, posing serious health risks due to their potential to induce DNA damage and cancer. Traditional genotoxicity assays, while valuable, are limited by insufficient sensitivity, specificity, and efficiency, particularly when applied to complex food matrices. This study introduces a multiparametric high-content analysis (HCA) for the detection of genotoxic substances in complex food matrices. The developed assay measures three genotoxic biomarkers, including γ-H2AX, p-H3, and RAD51, which enhances the sensitivity and accuracy of genotoxicity screening. Moreover, the assay effectively distinguishes genotoxic compounds with different modes of action, which not only offers a more comprehensive assessment of DNA damage and the cellular response to genotoxic stress but also provides new insights into the exploration of genotoxicity mechanisms. Notably, the five tested food matrices, including coffee, tea, pak choi, spinach, and tomato, were found not to interfere with the detection of these biomarkers under proper dilution ratios, validating the robustness and reliability of the assay for the screening of genotoxic compounds in the food industry. The integration of multiple biomarkers with HCA provides an efficient method for detecting and assessing genotoxic substances in the food supply, with potential applications in toxicology research and food safety.

Innovative disposable pipette extraction for concurrent analysis of fourteen psychoactive substances in drug users’ sweat

Innovative disposable pipette extraction for concurrent analysis of fourteen psychoactive substances in drug users’ sweat

Strategic design of magnetic ionic covalent organic frameworks incorporating amino acid ionic liquids for enhanced selectivity adsorption of benzimidazoles

Strategic design of magnetic ionic covalent organic frameworks incorporating amino acid ionic liquids for enhanced selectivity adsorption of benzimidazoles