Identification Of Substances Research Articles

Present Concepts, Advancements and Challenges in the Realm of Forensic Entomotoxicology

The utilization of Forensic Entomo-toxicology in cases involving poisoning-related deaths has gained prominence due to insects serving as an alternative source of evidence when conventional toxicological samples have deteriorated or become unavailable. Numerous research studies have successfully demonstrated the detection, identification, and quantification of drugs and toxic substances from insect specimens. This comprehensive review explores the role of insects as viable toxicological samples, outlines their collection and preservation methods, delves into the analysis employing various instrumental techniques, and examines emerging trends in analytical approaches. Additionally, the review sheds light on the limitations that impede the advancement of this field and offers insights into potential directions for future research. Furthermore, it explores the impact of poisons on insects used for estimating the postmortem interval.

A current insight and future perspective of edible bird nest as caviar of the east

Edible bird’s nest (EBN) is a highly valuable food product obtained from swiftlet nests, primarily those of the Aerodramus genus. Due to its purported health benefits and exceptional taste, EBN is often referred to as the “caviar of the East.” This abstract presents a comprehensive review of the current state of EBN research, focusing on its chemical composition, nutritional value, pharmacological effects, and safety considerations. The chemical composition of EBN is intricate and influenced by various factors, including bird species, geographic origin, nest collection time, and processing methods. It is primarily composed of proteins, polysaccharides, minerals, lipids, and a wide range of bioactive compounds such as sialic acid, amino acids, and antioxidants. Additionally, EBN has demonstrated antioxidant, anti-inflammatory, anti-tumor, and anti-aging properties attributed to these bioactive constituents. While EBN is generally considered safe for human consumption, it is essential to address concerns related to potential contaminants like heavy metals, microbial pathogens, and allergens. This review offers a comprehensive overview of previous research conducted on residual impurities that may be present in edible bird’s nests (EBNs). The review encompasses various aspects, including, the regulatory framework and associated concerns regarding EBNs, the levels of nitrite and nitrate detected in EBNs, the presence of bacteria, fungi, and mites in EBNs, the identification of allergenic substances in EBNs, and the presence of heavy metals and excessive mineral content at different stages of EBN processing, including raw uncleaned (RUC) EBNs, raw cleaned (RC) EBNs, and EBNs after undergoing treatment. Graphical abstract:

The Use of Multi-Probe Modulated Laser Radiation for the Identification of Substances' Clots in the Fluid Flow

Modern tools of water supply systems monitoring at enterprises or in the housing sector use laser liquid sensing systems. In this case, as a rule, laboratory analyses of the obtained liquid samples are used, as well as spectral analysis methods when scanning the liquid with light for different wavelengths. These approaches do not allow for real-time analysis of a moving fluid flow (flow analysis). The paper considers a version for constructing of a system for online detecting and identifying emergency clots of pollutants in a liquid stream using laser radiation. The basic principles of the system construction, the block diagram of the system structure and parameters for identification of clots of substances under study flowing in the pipelines of the sewage or water treatment system at industrial enterprises are given. When constructing the system, several wavelengths of laser radiation are used, simultaneously directed to the one point of the studied clot of the studied fluid flow. Light wavelengths are determined at the stage of preparation for the study. At this initial stage of the process, optical transmission spectra of substances that are a priori possible in the studied fluid flow are analyzed. The main criterion for wavelengths choose is difference in substances optical transmission spectra at the se selected wavelengths. For the possibility of technical separation of signals at different wavelengths of the emitting radiation, the radiation fluxes are modulated. Creation of standards for identification substances in fluid flow clusters is carried out in the form of lattice functions containing the components of the substance optical transmission spectrum at certain wavelengths of laser radiation. Modulation of radiation is proposed to be carried out by controlling the pumping of each emitters of the system. The proposed system will find application in the oil and gas, processing industry, water filtration and purification systems, industrial enterprises and agricultural processing enterprises.

Senses and Utility in the New Chemistry

The New Chemistry, as practised by its early proponents in late eighteenth-century France, is often associated with quantification and a move away from sensorial perceptions. In this paper, I argue that the sensory, far from being discarded by the practitioners of the New Chemistry, thrived in one of their major productions: the Annales de Chimie. Viewing the New Chemistry through its relation to the sensory highlights the diversity of chemical applications and offers a new way of examining the connection of chemistry to state and industrial actors. Chemists utilised a precise vocabulary which allowed them to productively interact on the subject of the senses. Sensorial impressions were used for distinct purposes, including the identification of substances, and to track the progress of ongoing chemical transformations. Most important, the senses were frequently tied to the purpose of chemical work. As chemists put their expertise in support of the state, industry, medicine, and commerce, they aimed to improve the sensory qualities of their objects of study, be they dairy products or fabric dyes. Remaining attuned to the senses, therefore, was an essential prerequisite of the New Chemistry's claim to utility.

HUMAN ONTOLOGY FROM THE VIEWPOINT OF ORTHODOX CHRISTIAN ANTHROPOLOGY AND THE PSYCHOANALYTIC APPROACH

Certainly for Orthodox Christian anthropology, the person - man is undoubtedly and unquestionably its most fundamental and main issue. In this sense, in the specific scientific opinion/work, various ontological constants are dealt with and studied in relation to its constitution, as mentioned basically in the development content of Orthodox Christian anthropology. In addition, an attempt is made to render the Ontology of the person in accordance with the opinion of the Most Reverend Metropolitan of Pergamum Ioannis Zizioulas. Among other things, an attempt is made to analyze and attribute the contribution of the Cappadocian Fathers in terms of the active explanation of the differences of the confusion that existed until then, regarding the identification of the terms substance and person and the shift of the context of the time towards the face. Finally, a comparison will be attempted between the assumptions that Orthodox Christian anthropology advocates for the person with some other theoretical approaches regarding the creation and evolution of the human entity. Regarding the method of writing the specific theological work, the thorough and careful study and discussion of theological texts and theoretical approaches regarding the importance of the formation of man based on Orthodox Christian anthropology is used. Under these circumstances, it is noted that this work constitutes a thorough study of the interpretations of human performance according to the view of Orthodox Christian anthropology.

Detection of the explosive nitroaromatic compound simulants with chemosensory systems based on quartz crystal microbalance and chemiresistive sensor arrays

The work is devoted to investigations of possibility of rapid detection and subsequent identification of explosive substances by using the arrays of two types of sensor elements: quartz crystal microbalances and chemiresistive electrodes. Thin layers of calixarene compounds and composites of electrically conductive polymers, respectively, were used as the sensitive coatings. Several types of nitroaromatic compounds from nitrotoluene series were chosen as simulants of explosive substances: O-Nitrotoluene (2-MNT) and Nitrobenzene (MNB), the concentration of these volatile compounds varied from 10 to 100 ppm. The observed detection threshold, depending on the type of analyzed explosive simulants, was within the range of 1 to 10 ppm for quartz crystal sensors with calixarene sensitive films, and the response time was within 10…20 s for quartz crystal sensors and up to 1 min for chemiresistive sensors. It has been shown that among the tested calixarenes there are samples with high selective sensitivity. The possibility of qualitative identification of explosives at relatively low concentrations by using the statistical methods of chemical patterns recognition (the so-called “electronic nose”) has been demonstrated.

Nontargeted analysis and comparison strategies for volatile and semivolatile substances in toys made of different materials

A nontargeted broad-spectrum analysis method for unknown volatile and semivolatile substances in toys was established by gas chromatography–Orbitrap high-resolution mass spectrometry. Based on the NIST spectrum library, unknown substances could be accurately identified by comprehensive scoring, retention index, chemical ionization, and fine comparison of ion fragments. For substances not included in the library, the molecular formulas of unknown substances were retrieved through online compound databases. Possible structural formulas were verified by high-resolution spectra and fragmentation mechanisms. Taking teether toys as an example, the substances differences of products made of different materials were compared through the digitization of chemical composition. Specifically, 59 substances were identified in 50 teether toys. The toys made of two different materials each had their own substance distribution, and the types and quantities of substances in thermoplastic polyurethanes samples were more than those in silicone samples. Substances with high risk included phenol, N-methylaniline, cyclohexanone, and 4-tert-amylphenol. This work can serve as a reference for the identification of unknown substances in toys and other products, as well as for the comparison the chemical composition of products made of different materials. Thus, this work has positive significance in promoting the quality and safety of toys and reducing chemical harm to children.

Making Every Single Puff Count-Simple and Sensitive E-Cigarette Aerosol Sampling for GCxIMS and GC-MS Analysis.

The analysis of the aerosol from tobaccoless electronic cigarettes (e-cigarettes) is an important part of understanding their impact on human health, yet sampling aerosol from e-cigarettes is still considered a challenge. It lacks a standard method for research and quality control and there are a variety of methods. However, few are simple and inexpensive, and none have been suggested for the use with gas chromatography coupled ion mobility spectrometry (GCxIMS). This work presents and evaluates such a setup made from standard lab equipment to quickly collect a quantitative sample from the aerosol of a single puff (5 s totaling 125 mL). The aerosol condensates directly in the cooled headspace (HS) vial, which is analyzed in the HS-GCxIMS or mass spectrometer (HS-GC-MS). The combined use of GC-MS and GCxIMS allows the simple and sensitive identification of unknown substances in complex mixtures and the identification of degradation products in the aerosols. A calibration of 26 flavor compounds (0.2-20 µg/g) was created using single puffs of a spiked, flavorless commercial refill solution and 2-alkanones as internal standards. This sensitive but easily reproducible setup enables a wide range of further investigations, even for labs that were previously unable to afford it.

Spectral identification of cannabinoids

The combination of infrared spectroscopy and chemometrics has become a popular method of detection and / or identification of illicit substances. This review paper highlights the most frequently used analytical tools in this research area, focusing on the identification of synthetic or natural cannabinoids.

P01-07: EFSA activities in the development of Adverse Outcome Pathways for the identification of substances having endocrine disruption properties

P01-07: EFSA activities in the development of Adverse Outcome Pathways for the identification of substances having endocrine disruption properties

Histochemical Staining of Plant Tissues

Histochemistry is a subfield of histology that focuses on identifying the chemical components of cells and tissues. Starch deposition occurs throughout the plant body, but seeds, the parenchyma of secondary vascular tissues in the stem and root, tubers, rhizomes, and maize are notably affected. The protoplast's main ergastic components are starch and proteins. Tannin, a diverse collection of phenol derivatives that are usually related to glucosides, is prevalent in the leaves (xylem) of many plants. Saponins are a type of saponin that is extremely rare. Fats are broadly dispersed throughout the plant body, and they are likely present in minute quantities in each plant cell. Fats are a common reserve resource in meristematic cells such as seeds, spores, and embryos. The breakdown product of carbohydrates is glucosides. Alkaloids are the byproducts of protein breakdown. Many plants have secondary products that are medicinally valuable. Using stains, markers, and light and electron microscopy, histochemistry studies the identification and distribution of chemical substances within and between biological cells. Histochemistry is a methodological approach that allows the chemical analysis of cells and tissues in relation to their structural organisation , but for plant secretory structures, a broad histochemical analysis is required because the same gland and even the same glandular cell can produce multiple metabolites at the same time.

Monte Carlo simulations of the underwater detection of illicit war remnants with neutron-based sensors

In recent years, the demand for accurate detection and identification of hazardous substances in an aquatic environment, especially in the Baltic Sea, has seen a significant rise, with a specific focus on unexploded ordnance (UXO) containing conventional explosives and various chemical agents, including, but not limited to, mustard gas, Clark I and II and other lethal compounds. These substances pose a significant threat to human health and the environment, and their identification is crucial for effective demining and environmental protection efforts. In this article, a novel approach for fast, remote, and non-destructive recognition of dangerous substances based on a SABAT sensor installed on an ROV is described. The performance of the proposed neutron-based sensor in an aquatic environment was verified based on a series of Monte Carlo simulations for mustard gas, Clark I and II, and TNT, as they are the most common chemical threats at the bottom of the Baltic Sea. The sensor’s ability to accurately discriminate hazardous and non-hazardous materials is described in the paper in terms of the ratio of chlorine to hydrogen (Cl/H), carbon to oxygen (C/O), and nitrogen to hydrogen (N/H) activation lines integrals. The authors also discussed the future directions of work to validate SABAT (Stoichiometry Analysis By Activation Techniques) sensors in the operational environment.

Exploiting the potential of fabric phase sorptive extraction for forensic food safety: Analysis of food samples in cases of drug facilitated crimes

Drug-facilitated crimes (DFCs) entail the use of a single drug or a mixture of drugs to render a victim unable. Traditionally, biological samples have been gathered from victims and conducting analysis to establish evidence of drug administration. Nevertheless, the rapid metabolism of various drugs and delays in analysis can impede the identification of such substances. For this, the present article describes a rapid, sustainable, highly efficient and miniaturized protocol for the identification and quantification of three sedative-hypnotic drugs namely diazepam, chlordiazepoxide and ketamine in alcoholic beverages and complex food samples (cream of biscuit, flavoured milk, juice, cake, tea, sweets and chocolate). The methodology involves utilizing fabric phase sorptive extraction (FPSE) to extract diazepam (DZ), chlordiazepoxide (CDP), and ketamine (KET), Subsequently, the extracted sample are subjected to analysis using gas chromatography-mass spectrometry (GC–MS). Several parameters, including type of membrane, pH, agitation time and speed, ionic strength, sample volume, elution volume and time, and type of elution solvent, were screened and thoroughly optimized. Sol-gel Carbowax 20M (CW-20M) has demonstrated most effective extraction efficiency for the target analytes among all evaluated membranes. Under optimal conditions, the method displayed linearity within the range of 0.3–10 µg mL−1 (or µg g−1), exhibiting a coefficient of determination (R2) ranging from 0.996 to 0.999. The limits of detection (LODs) and limits of quantification (LOQs) for liquid samples ranging between 0.020 and 0.069 µg mL−1 and 0.066–0.22 µg mL−1, respectively. Correspondingly, the LODs for solid samples ranged from 0.056 to 0.090 µg g−1, while the LOQs ranged from 0.18 to 0.29 µg g−1. Notably, the method showcased better precision, with repeatability and reproducibility both below 5% and 10%, respectively. Furthermore, the FPSE-GC–MS method proved effective in determining diazepam (DZ) in forensic food samples connected to drug-facilitated crimes (DFCs). Additionally, the proposed method underwent evaluation for its whiteness using the RGB12 algorithm.

A data-derived reference mixture representative of European wastewater treatment plant effluents to complement mixture assessment

Aquatic environments are polluted with a multitude of organic micropollutants, which challenges risk assessment due the complexity and diversity of pollutant mixtures. The recognition that certain source-specific background pollution occurs ubiquitously in the aquatic environment might be one way forward to approach mixture risk assessment. To investigate this hypothesis, we prepared one typical and representative WWTP effluent mixture of organic micropollutants (EWERBmix) comprised of 81 compounds selected according to their high frequency of occurrence and toxic potential. Toxicological relevant effects of this reference mixture were measured in eight organism- and cell-based bioassays and compared with predicted mixture effects, which were calculated based on effect data of single chemicals retrieved from literature or different databases, and via quantitative structure-activity relationships (QSARs). The results show that the EWERBmix supports the identification of substances which should be considered in future monitoring efforts. It provides measures to estimate wastewater background concentrations in rivers under consideration of respective dilution factors, and to assess the extent of mixture risks to be expected from European WWTP effluents. The EWERBmix presents a reasonable proxy for regulatory authorities to develop and implement assessment approaches and regulatory measures to address mixture risks. The highlighted data gaps should be considered for prioritization of effect testing of most prevalent and relevant individual organic micropollutants of WWTP effluent background pollution. The here provided approach and EWERBmix are available for authorities and scientists for further investigations. The approach presented can furthermore serve as a roadmap guiding the development of archetypic background mixtures for other sources, geographical settings and chemical compounds, e.g. inorganic pollutants.

ИССЛЕДОВАНИЕ ВОЗМОЖНОСТИ ПРИМЕНЕНИЯ СИСТЕМЫ КОБАЛЬТ - ФТАЛЕКСОН SA КАК РЕАГЕНТА НА КОФЕИН-БЕНЗОАТ НАТРИЯ

The development of new and increasing the sensitivity of already known techniques of high quality and quantitative definition of medicinal substances is one of pharmaceutical chemistry problems. This 
 paper presents the results of a study of the interaction of sodium caffeine benzoate with phthalexone SA in the 
 presence of cobalt ions. It has been shown that the identification of this drug substance, as well as its quanti tative determination by reaction with the Co2 +
 - phthalexone SA system, is possible in highly acidic media. 
 The use of the Co2 +
 - phthalexone SA complex was confirmed in an experiment using aqueous analytical 
 systems.

Developing machine learning approaches to identify candidate persistent, mobile and toxic (PMT) and very persistent and very mobile (vPvM) substances based on molecular structure

Determining which substances on the global market could be classified as persistent, mobile and toxic (PMT) substances or very persistent, very mobile (vPvM) substances is essential to prevent or reduce drinking water contamination from them. This study developed machine learning models based on different molecular descriptors (MDs) and defined applicability domains for the screening of PMT/vPvM substances. The models were trained with 3111 substances with expert weight-of-evidence based PMT/vPvM hazard classifications that considered the highest quality data available. The model was based on the hypothesis that PMT/vPvM substances contain similar MDs, representative of chemical structures resistant to degradation, be associated with low sorption (or high-water solubility) and in some cases be associated with known toxic mechanisms. All possible model combinations were tested by integrating different molecular description methods, data balancing strategies and machine learning algorithms. Our model allows one-step prediction of candidate PMT/vPvM substances, and our method was compared with the approach predicting P, M and T separately (i.e. three-step prediction). The results showed that the one-step model achieved a higher accuracy of 92% for PMT/vPvM identification (i.e. positive samples) for an internal test set, and also resulted in a higher accuracy of 90% for an external test set of chemical pollutants detected in Taihu Lake, China. Furthermore, prediction mechanism of the model was interpreted by Shapley additive explanations (SHAP). This work presents an advance of big data in silico screening models for the identification of substances that potentially meet the PMT/vPvM criteria.

Pure and doped carbon quantum dots as fluorescent probes for the detection of phenol compounds and antibiotics in aquariums

The resulting antibiotic residue and organic chemicals from continuous climatic change, urbanization and increasing food demand have a detrimental impact on environmental and human health protection. So, we created a unique B, N-CQDs (Boron, Nitrogen doping carbon quantum dots) based fluorescent nanosensor to investigate novel sensing methodologies for the precise and concentrated identification of antibiotics and phenol derivatives substances to ensure that they are included in the permitted percentages. The as-prepared highly fluorescent B, N-CQDs had a limited range of sizes between 1 and 6 nm and average sizes of 2.5 nm in our study. The novel B, N-CQDs showed high sensitivity and selectivity for phenolic derivatives such as hydroquinone, resorcinol, and para aminophenol, as well as organic solvents such as hexane, with low detection limits of 0.05, 0.024, 0.032 and 0.013 µM respectively in an aqueous medium. The high fluorescence B, N-CQDs probes were examined using transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and UV/VIS spectroscopy. The outcomes were compared to carbon quantum dots (CQDs) previously generated from Urea.

Machine learning-driven grating-like SERS Platform toward ultra-sensitive detection of forsythin

Due to the complexity of existing substrate preparation processes and the poor reproducibility of substrates prepared from a single material, a highly reliable and low-cost Ag20/V–Ti20/DVD multi-stage composite SERS substrate was constructed in this study. The grating-like SERS substrate has an enhancement factor of 8.44×106 for R6G and a detection limit as low as 1×10−10 M. Results indicated that the highly regular grating-like SERS substrate exhibited excellent reproducibility with the relative standard deviation (RSD) values less than 10%. The three-dimensional finite-difference time-domain (3D-FDTD) method simulated the spatial distribution of the electric field intensity of the substrate, and a large number of “hot spot” regions were distributed in the Ag nanogap in the grating structure nanostructure. The optimized substrate was subsequently utilized for the discrimination of R6G with different concentrations using SERS and machine learning methods. These outstanding SERS properties of the Ag20/V–Ti20/DVD multi-stage SERS sensing platform suggested its potential application in the identification of pharmacodynamic substance in forsythin when the concentration as low as 1×10−7 g/l. At the same time, the highly ordered grating structure provided a new idea for the preparation of regular nanoarray substrates, and the combination of SERS and machine learning paved a new way toward the ultra-sensitive detection of other pharmacodynamic substances in traditional Chinese medicine (TCM).

Identification of an Unknown Substance by the Methods of Multi-Energy Pulse X-ray Tomography

The inverse problem for the non-stationary radiative transfer equation is considered, which consists in finding the attenuation coefficient according to the pulsed multi-energy X-ray exposure. For a short duration of the probing pulse, the asymptotic solution of the inverse problem is found. The problem of identifying an unknown substance by attenuation coefficients approximately found on a finite set of energy values is formulated. Algorithms for solving identification problems are proposed. The results of the numerical simulation are presented for a wide range of substances of interest in medical computed tomography.

Phthalate acid esters contribute to the cytotoxicity of mask leachate: Cell-based assay for toxicity assessment

After the COVID-19 outbreak, masks have become an essential part of people lives. Although several studies have been conducted to determine the release of hazardous substances from masks, how their co-presence poses a potential exposure risk to human health remains unexplored. In this study, we quantitatively compared the leaching of substances from six different common types of masks, including phthalate acid esters (PAEs), metals, and microplastics (MPs), and comprehensively evaluated the potential cytotoxicity of different leachates. MPs smaller than 3 µm were quantified by Py-GC-MS, and reusable masks showed greater releasing potentials up to 1504 µg/g. We also detected the prevalence of PAEs in masks, with the highest release reaching 42 μg/g, with dibutyl phthalate (DBP), diisobutyl phthalate (DiBP) and bis (2-ethylhexyl) phthalate (DEHP) being the predominant types. Moreover, the antimicrobial cloth masks released 173.0 µg of Cu or 4.5 µg of Ag, representing 2.7% and 0.04% of the original masks, respectively. Our cell-based assay results demonstrated for the first time that mask leachate induced nuclear condensation with DNA damage, and simultaneously triggered high levels of glutathione and reactive oxidative stress production, which exacerbated mitochondrial fragmentation, eventually leading to cell death. Combined with substance identification and correlation analysis, PAEs were found to be the contributors to cytotoxicity. Masks containing Cu or Ag led to acidification of lysosomes and alkalinization of cells. These results strongly suggested that the levels of PAEs in the production of regulatory masks should be strictly controlled.