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A novel electrochemical sensor based on multi-walled carbon nanotubes doped with vanadium pentoxide/telluride (MWCNTs@V 2 O 5 /Te) was developed for the detection and quantification of morphine sulfate in real biological samples. MWCNTs@V 2 O 5 /Te nanocomposite was functionalized with cysteamine as a linker, to create thiol interaction with the -OH group of the MWCNTs@V 2 O 5 /Te nanocomposite at one end, and free -NH 2 group interaction with the -OH group on morphine sulfate, on the other end. This modification enhances the conjugation capability of morphine sulfate with the fabricated biosensor. (MWCNTs@V 2 O 5 /Te-Cys/GCE). MWCNTs@V 2 O 5 /Te nanocomposite morphological and structural analysis is carried out by SEM, TEM, EDX, FTIR, and UV-Vis spectroscopy. At varying concentrations and pH levels, the electrochemical sensor response of the modified electrode is investigated using cyclic voltammetry (CV). To validate the findings, differential pulse voltammetry (DPV), electrochemical impedance spectroscopy (EIS), and chronoamperometry are employed to investigate morphine sulfate detection, yielding excellent results in real biological samples. The fabricated sensor, as indicated by the calibration curve, exhibits a wide linear range of 10–60 µM and a limit of detection (LOD) of 0.01 µM by DPV. These results reveal that this novel sensor is highly stable, sensitive, and reproducible for detecting morphine sulfate. Therefore, this developed sensing platform can be used in clinical diagnostics, narcotics detection, and forensic analysis.

3-Chloromethcathinone (3-CMC) is a synthetic cathinone that has been identified as a new psychoactive substance (NPS) by the European Monitoring Centre for Drugs and Drug Addiction. Despite its increasing prevalence in the recreational drug market since 2014, scientific literature on 3-CMC remains limited. This study employed a multi-step approach to investigate 3-CMC metabolism. First, an in-silico prediction was conducted to compile a list of potential metabolites. Then, in vitro assays were performed using human liver microsomes at two concentrations of 3-CMC. Samples were analyzed using an ultra-performance liquid chromatography system coupled with a high-resolution mass spectrometer. Chromatographic separation was obtained with an Acquity UPLC HSS C18 1.8 µm, 2.1 × 150 mm column on an Ultimate 3000 system chromatography coupled with a QExactivePlus mass spectrometer). Finally, data mining for metabolite identification was conducted using Compound Discoverer software. The combined in silico and in vitro approaches identified four primary metabolites of 3-CMC in HLM assays:1) hydroxylation of the aliphatic group to give M1 2) followed by reduction of the β-keto group, yielding M4; 3) N-demethylation, affording M2; and 4) Reduction of the β-keto group, yielding M3. Subsequent analysis of biological samples from two postmortem cases revealed that urine was the most informative matrix for detecting 3-CMC and its metabolites. The M3 metabolite, was identified as the third abundant metabolite in human liver microsome but was identified as the predominant metabolite in human postmortem samples. Identifying these key metabolites is crucial for improving the accuracy of forensic investigations and extending the detection window beyond the parent compound. [Display omitted] •Novel insights into 3-CMC metabolism using advanced in silico and in vitro methods.•Findings reveal distinct 3-CMC metabolic patterns in postmortem biological matrices.•M4 metabolite identification extends detection window for forensic investigations.

Liquid chromatography-mass spectrometry (LC–MS) has emerged as a powerful analytical technique for analyzing complex biological samples. Among various chromatographic stationary phases, porous graphitic carbon (PGC) columns have attracted significant attention due to their unique properties—such as the ability to separate both polar and non-polar compounds and their stability through all pH ranges and to high temperatures—besides the compatibility with LC–MS. This review discusses the applicability of PGC for SPE and separation in LC–MS-based analyses of human biological samples, highlighting the diverse applications of PGC-LC–MS in analyzing endogenous metabolites, pharmaceuticals, and biomarkers, such as glycans, proteins, oligosaccharides, sugar phosphates, and nucleotides. Additionally, the fundamental principles underlying PGC column chemistry and its advantages, challenges, and advances in method development are explored. This comprehensive review aims to provide researchers and practitioners with a valuable resource for understanding the capabilities and limitations of PGC columns in LC–MS-based analysis of human biological samples, thereby facilitating advancements in analytical methodologies and biomedical research.

This paper introduces an enhanced technique for analyzing iron isotopes in complex marine and biological samples. A dedicated iron purification method for biological marine matrices, utilizing three ion exchange columns, is validated. The MC-ICPMS in pseudo-high-resolution mode determines precise iron isotopic ratios, with sensitivity improved through the DSN-100 desolvating nebulizer system and Apex-IR. Only 2 µg of iron on DSN versus 1 µg on Apex is needed for six replicates (30–60 times improvement) while 10 to 20 µg is required for a single measurement on a wet system considering the resolution power (Rp) is maintained at 11,000–13,000. The Ni-doping method with a Fe/Ni ratio of 1 yields more accurate isotopic ratios than standard-sample bracketing alone. Measurement reproducibility of triplicate samples from marine biological experiments on MC-ICPMS is ± 0.03‰ (2SD) for δ56Fe and ± 0.07‰ for δ57Fe (2SD). This study introduces a novel iron purification process specifically designed for marine and biological samples, enhancing sensitivity and enabling more reliable measurements with smaller sample sizes and reduced uncertainties. It proposes iron isotopic compositions for biological reference materials, offering a valuable reference dataset in diverse scientific disciplines.

The application of nanomaterials is leading to innovative developments in industry, agriculture, consumer products, and food and related sectors. However, due to the special properties of these materials there are concerns about their safety, especially because of our limited knowledge of human health effects and the fact that constantly new nanomaterials and applications thereof are being produced. The development of analytical techniques is a key element to understand the benefits as well as the risks of the application of such materials. In this study, a method is developed and validated for sizing and quantifying nano-silver in chicken meat using single particle inductive coupled plasma mass spectrometry (ICP-MS). Samples are processed using an enzymatic digestion followed by dilution of the digest and instrumental analysis of the diluted digest using single particle ICP-MS. Validation of the method in the concentration of 5–25 mg/kg 60-nm silver nanoparticles showed good performance with respect to trueness (98–99 % for size, 91–101 % for concentration), repeatability (<2 % for size, <11 % for concentration), and reproducibility (<6 % for size, <16 % for concentration). The response of the method is linear, and a detection limit as low as 0.1 mg/kg can be obtained. Additional experiments showed that the method is robust and that digests are stable for 3 weeks at 4 °C. Once diluted for single particle ICP-MS analysis, the stability is limited. Finally, it was shown that nano-silver in chicken meat is not stable. Silver nanoparticles dissolved and were transformed into silver sulfide. While this has implications for the form in which nano-silver will be present in real-life meat samples, the developed method will be able to determine the presence and quantity of nanoparticle silver in such samples.

There is growing interest in recovering analytes other than DNA from evidentiary samples. mRNA markers can help identify body fluids, link body fluid to a contributor via coding SNPs, and estimate Post-Mortem Interval. Proteins, which in many cases are more abundant and resistant to degradation than RNA and DNA, offer the possibility for human individualization via Genetically Variant Peptides and are also useful for body fluid identification, but are routinely destroyed during nucleic acid extraction. We report a novel trace sample recovery method which uses paramagnetic beads conjugated with salmon protamine that bind nucleic acids with very high efficiency under buffer conditions which keep proteins intact. After performing a mild lysis step, nucleic acids are bound to the beads, unbound proteins are collected in the supernatant, and bound nucleic acids are then eluted separately. We demonstrate recovery of DNA, RNA, and protein from 1 µL blood, 1 µL semen, and 2 µL saliva, as well as successful downstream processing using STR DNA profiling, body fluid specific mRNA detection, and protein identification. Amounts of DNA recovered from semen and saliva were on par with a bead-based commercial kit that lacks coordinated RNA and intact protein recovery. Recovered DNA yields from blood were reduced compared to the commercial kit but still sufficient for all downstream processing. RNA amounts recovered were significantly higher in all body fluids using our method. This is the first multianalyte recovery method suitable for trace biological samples, which once validated, will offer forensic scientists the entire suite of molecular analytes for analysis. •Novel method for co-recovery of DNA, RNA and proteins from trace biological samples.•Successful downstream processing of extracted DNA, RNA, and protein from 1 µL blood, 1 µL semen, and 2 µL saliva.•Once validated, method will offer forensic scientists suite of molecular analytes.

Canine distemper, a viral disease with a global impact on various animals including dogs, foxes, wolves, lions, and leopards, requires early diagnosis for effective treatment and outbreak control. Common laboratory methods, such as enzyme-linked immunosorbent assay, polymerase chain reaction, and viral isolation, face challenges such as extended turnaround times, high costs, and the expertise required. This study has developed a field-based biosensor for detecting the canine distemper virus (CDV), utilising a screen-printed carbon electrode (SPCE) and a computer-assisted portable potentiostat. A 30-mer oligonucleotide capture probe, designed using Primer3 Plus software version 3.3.0, detected hybridisation with the CDV complementary strand through electrochemical analysis via differential pulsed voltammetry. The developed biosensor exhibited good linearity in quantifying the target analyte concentration (0.1 to 12.8 µM), with a detection limit of 0.05 µM, indicating high sensitivity. Specificity tests using complementary and non-complementary sequences confirmed the biosensor’s accuracy. The electrode can be reused up to eight times with a residual capacity of 93.72 ± 5.45% after regeneration using a 50 mM NaOH solution. The developed biosensor was also used to detect CDV in biological samples after RNA extraction and amplification. Results from the biosensor aligned with those from reverse transcriptase polymerase chain reaction (RT-PCR) findings, showing 100% agreement. These findings support the potential development of a field-deployable portable device for effectively diagnosing canine distemper in biological samples.

In this study, magnetic cobalt ferrite/graphene oxide (CoFe 2 O 4 /GO) sorbent was synthesized and used in magnetic dispersive micro-solid phase extraction (MD-µ-SPE) combined to spectrofluorometric as a green, precise, and effective method to separate and detect of vitamin B9 in food and biological samples. The structure, morphology and magnetic properties of CoFe 2 O 4 /GO nanocomposite was characterized by Fourier transform infrared (FT-IR) spectroscopy, X-Ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM), and vibrating sample magnetometer (VSM). Four parameters of pH, sorbent dose, temperature, and sonication time were selected as effective variables on the process and optimized by central composite design (CCD). Under optimized conditions, the linear range, limit of detection, intra-day (repeatability) and inter-day (intermediate) precision were obtained 15–750 ng mL −1 , 3.96 ng mL −1 , 3.3–3.8%, and 4.2–4.9%, respectively. The material’s antimicrobial potency also evaluated, showcasing notable inhibitory action against both Gram-negative Escherichia coli bacteria, with a zone of inhibition measuring 17.5 mm at the highest concentration, and Gram-positive Staphylococcus aureus bacteria, which displayed a 14.5 mm ZIO at similar concentrations. To the best of our knowledge, this is the first report on using CoFe₂O₄/GO for vitamin B9 extraction and detection. This work introduces a novel, eco-friendly, and effective analytical platform that combines the magnetic properties of CoFe 2 O 4 with the high surface area and functional groups of GO for targeted vitamin analysis. These results demonstrate that the synthesized nanocomposite possesses both excellent adsorption capability and antibacterial activity.

Inductively coupled plasma mass spectrometry in single-particle mode (spICPMS) is a promising method for the detection of metal-containing nanoparticles (NPs) and the quantification of their size and number concentration. Whereas existing studies mainly focus on NPs suspended in aqueous matrices, not much is known about the applicability of spICPMS for determination of NPs in complex matrices such as biological tissues. In the present study, alkaline and enzymatic treatments were applied to solubilize spleen samples from rats, which had been administered 60-nm gold nanoparticles (AuNPs) intravenously. The results showed that similar size distributions of AuNPs were obtained independent of the sample preparation method used. Furthermore, the quantitative results for AuNP mass concentration obtained with spICPMS following alkaline sample pretreatment coincided with results for total gold concentration obtained by conventional ICPMS analysis of acid-digested tissue. The recovery of AuNPs from enzymatically digested tissue, however, was approximately four times lower. Spiking experiments of blank spleen samples with AuNPs showed that the lower recovery was caused by an inferior transport efficiency of AuNPs in the presence of enzymatically digested tissue residues.