Sample Processing Methods Research Articles

Development of a UHPLC-MS/MS Method for the Determination of Moxidectin in Rat Plasma and Its Application in Pharmacokinetics.

The aim of the present study was to establish a simple and reliable ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method and apply it for the determination of pharmacokinetics of moxidectin-loaded microspheres (MOX-MS) in rats. Plasma samples were processed using a simplified liquid-liquid extraction method and were separated using an Agilent Zorbax Eclipse Plus C18 column (50 mm × 2.1 mm, 1.8 μm) with a mobile phase consisting of a 10 mM ammonium formate solution with 0.1% formic acid (A) and acetonitrile (B) at a flow rate of 0.4 mL/min for 5 min. Avermectin B1a was used as an internal standard (IS). The sample was injected at a volume of 10 μL with a column temperature of 35 °C and detected in a positive ion mode. A good linear response across the concentration range of 1.00-200 ng/mL (r2 > 0.99) and a lower limit of quantification (LLOQ) of 1.00 ng/mL were achieved. The extraction recovery of moxidectin exceeded 94.1%, the matrix effect was between 91.2% and 96.2%, the accuracy ranged from 100.1 to 103.6%, and the relative standard deviation (RSD) did not exceed 15% for the intra- and inter-day accuracy and precision. The pharmacokinetic results showed that MOX-MS significantly decreased Cmax, prolonged T1/2, and improved bioavailability. The developed method significantly reduced the assay volume, shortened detection time, simplified sample processing methods and saved assay costs, which may contribute to the development of the new antiparasitic drug.

Clinical utility of plasma cell-free DNA (cfDNA) in diffuse gliomas for the detection of IDH1 R132H mutation

Liquid biopsy for CNS tumors is in its nascent phase, hindered by the low levels of circulating tumor DNA (ctDNA). Overcoming this challenge requires highly sensitive molecular techniques. DD-PCR emerges as a standout technique due to its ability to identify rare mutations, copy number variations, and circulating nucleic acids, making it one of the best methods for identifying somatic mutations in cell-free DNA (cfDNA). Despite promising results from various studies demonstrating the feasibility of obtaining informative ctDNA profiles from liquid biopsy samples, challenges persist, including the need to standardize sample collection, storage, and processing methods, define clear assay positivity thresholds, and address the overall low assay sensitivity. Our two-phase study began by assessing DD-PCR efficacy in FFPE tissues, revealing robust concordance with immunohistochemistry. In Phase 1 (85 cases), DD-PCR on FFPE tissues demonstrated 100 % sensitivity and specificity for IDH1 R132H mutations. In Phase 2 (100 cases), analysis extended to cfDNA, maintaining high specificity (100 %) with moderate sensitivity (44.2 %). Overall concordance with immunohistochemistry was 61 %, highlighting liquid biopsy's potential in glioma management. The findings emphasized DD-PCR's clinical utility in both tissue and liquid biopsy, underscoring its role in early detection, diagnosis, and therapeutic monitoring of diffuse gliomas.

Interlaboratory Evaluation of Bretziella fagacearum Molecular Detection Assays to Guide the eDNA Monitoring of Oak Wilt Disease

ABSTRACTOak wilt disease, caused by the fungus Bretziella fagacearum, can kill mature red oaks within months of infection, severely affecting biodiversity, landscapes, and industries. The disease, originally only present in the United States, was officially reported for the first time in Canada in June 2023. The aim of this study was to suggest a standardized assay and sample processing method to optimize oak wilt detection both in infection centers and ahead of the disease front. Two previously published molecular assays, a Nested PCR and a TaqMan qPCR, were compared to detect B. fagacearum in a variety of samples in a ring trial across five laboratories. Sample types investigated included eDNA from trapped insect vectors (sorted insects and bulk content from traps), infested and healthy oak wood chips, and B. fagacearum conidia dilutions. Results demonstrated that both Nested and TaqMan assays can be used for molecular confirmation of oak wilt, and results are reproducible across different labs. There is a general agreement between both detection assays when testing true‐positive and true‐negative samples. Both methods demonstrated overall good accuracy. The TaqMan assay was more sensitive and detected lower amounts of DNA target. Both tests were 100% specific to oak wood samples, which was the best sample type to use for detection. In general, samples with high Cts were more prompted to yield false negative Nested results. Detecting oak wilt from bulk insect samples was by far more rapid than sorted sap beetles, but resulted in lower detection signals, especially with the Nested assay. The time‐period when the insect traps were set up also had considerable influence on detection results. We hope this study helps to formulate guidelines in oak wilt detection and biosurveillance management.

MicroRNA as Sepsis Biomarkers: A Comprehensive Review.

Sepsis, a life-threatening condition caused by the body's dysregulated response to infection, presents a significant challenge in clinical management. Timely and accurate diagnosis is paramount for initiating appropriate interventions and improving patient outcomes. In recent years, there has been growing interest in identifying biomarkers that can aid in the early detection and prognostication of sepsis. MicroRNAs (miRNAs) have emerged as potential biomarkers for sepsis due to their involvement in the regulation of gene expression and their stability in various biological fluids, including blood. MiRNAs are small non-coding RNA molecules that play crucial roles in post-transcriptional gene regulation by binding to target messenger RNAs (mRNAs), leading to mRNA degradation or translational repression. The diagnostic and prognostic potential of miRNAs in sepsis stems from their ability to serve as sensitive and specific biomarkers reflective of the underlying pathophysiological processes. Compared to traditional biomarkers such as C-reactive protein (CRP) and procalcitonin (PCT), miRNAs offer several advantages, including their early and sustained elevation during sepsis, as well as their stability in stored samples, making them attractive candidates for clinical use. However, despite their promise, the clinical translation of miRNAs as sepsis biomarkers faces several challenges. These include the need for standardized sample collection and processing methods, the identification of optimal miRNA panels or signatures for differentiating sepsis from other inflammatory conditions, and the validation of findings across diverse patient populations and clinical settings. In conclusion, miRNAs hold great promise as diagnostic and prognostic biomarkers for sepsis, offering insights into the underlying molecular mechanisms and potential therapeutic targets. However, further research is needed to overcome existing challenges and realize the full clinical utility of miRNAs in improving sepsis outcomes.

A case of mistaken identity: a systematic review, meta-analysis, and reinvestigation of hemotropic Mycoplasma spp. infection in Ctenocephalides felis (cat flea)

Background Feline-associated hemotropic Mycoplasma (hemoplasmas) are believed to be transmitted by two primary mechanisms: (1) direct transmission via fighting and (2) vector-borne transmission by the cat flea (Ctenocephalides felis). While the efficiency of transmission by C. felis appears low, most manuscripts focus on the prevalence of hemoplasmas in wild-caught fleas and report either a very low (< 3%) or a high (> 26%) prevalence. Therefore, we aimed to assess the influence of sample processing and PCR methods on C. felis hemoplasma infection prevalence. MethodsA systemic review of PubMed articles identified 13 manuscripts (1,531 fleas/flea pools) that met the inclusion criteria (performed PCR for >1 hemoplasma on C. felis collected from cats). Risk of bias was assessed utilizing the ROBINS-E tool. Meta-analysis performed in R of these manuscripts found that not washing samples and a common set of 16S rRNA primers first published in Jensen et al. 2001 were associated with increased hemoplasma prevalence. To evaluate the influence of washing on newly collected fleas, we assessed the hemoplasma status of 20 pools of 5 C. felis each, half of which were washed and half not washed.ResultsFlea washing did not influence the detection of hemoplasma but instead amplified Spiroplasma. To assess non-specific amplification with the Jensen et al. 2001 primers, 67 C. felis samples (34% previously reported hemoplasma infected) were subject to PCR and sequencing. By this method, hemoplasma was detected in only 3% of samples. In the remaining “hemoplasma infected” fleas, PCR amplified Spiroplasma or other bacteria. ConclusionsTherefore, we concluded that hemoplasma infection in C. felis is rare, and future flea prevalence studies should sequence all positive amplicons to validate PCR specificity. Further investigation of alternative methods of feline-associated hemoplasma transmission and the ability of C. felis to maintain hemoplasma infection is necessary.Graphical

Sequential extraction, depolymerization and quantification of polyethylene terephthalate nanoplastics using magnetic ZIF-8 nanocomposites

The detection and quantification of nanoplastics in aqueous medium is largely untapped because of an absence of appropriate sample processing methods. In this work, magnetic ZIF-8 nanoparticles (Nano-Fe@ZIF-8) have been applied for the magnetic extraction and depolymerization of polyethylene terephthalate (PET) nanoplastics. Nano-Fe@ZIF-8 enabled the fast aggregation and magnetic retrieval of PET nanoplastics from water. The Zn(II) present in Nano-Fe@ZIF-8 subsequently acted as a catalyst for the depolymerization of the extracted PET nanoplastics using ethylene glycol at 180 °C. PET nanoplastics were depolymerized in just 30 min, producing the depolymerization product bis(2-hydroxyethyl) terephthalate. The selective quantification of the depolymerization product using reversed-phase liquid chromatography enabled the measurement of the original PET nanoplastics present in water at parts-per-million level, and with a high reproducibility (RSD, 2.8–5.9 %). This is the first example of an integrated magnetic-catalytic nanomaterial enabling the isolation, depolymerization, and detection of nanoplastics from aqueous medium.

Removing unwanted variation between samples in Hi-C experiments.

Hi-C data are commonly normalized using single sample processing methods, with focus on comparisons between regions within a given contact map. Here, we aim to compare contact maps across different samples. We demonstrate that unwanted variation, of likely technical origin, is present in Hi-C data with replicates from different individuals, and that properties of this unwanted variation change across the contact map. We present band-wise normalization and batch correction, a method for normalization and batch correction of Hi-C data and show that it substantially improves comparisons across samples, including in a quantitative trait loci analysis as well as differential enrichment across cell types.

Evaluating and optimizing Acid-pH and Direct Lysis RNA extraction for SARS-CoV-2 RNA detection in whole saliva

COVID-19 has been a global public health and economic challenge. Screening for the SARS-CoV-2 virus has been a key part of disease mitigation while the world continues to move forward, and lessons learned will benefit disease detection beyond COVID-19. Saliva specimen collection offers a less invasive, time- and cost-effective alternative to standard nasopharyngeal swabs. We optimized two different methods of saliva sample processing for RT-qPCR testing. Two methods were optimized to provide two cost-efficient ways to do testing for a minimum of four samples by pooling in a 2.0 mL tube and decrease the need for more highly trained personnel. Acid-pH-based RNA extraction method can be done without the need for expensive kits. Direct Lysis is a quick one-step reaction that can be applied quickly. Our optimized Acid-pH and Direct Lysis protocols are reliable and reproducible, detecting the beta-2 microglobulin (B2M) mRNA in saliva as an internal control from 97 to 96.7% of samples, respectively. The cycle threshold (Ct) values for B2M were significantly higher in the Direct Lysis protocol than in the Acid-pH protocol. The limit of detection for N1 gene was higher in Direct Lysis at ≤ 5 copies/μL than Acid-pH. Saliva samples collected over the course of several days from two COVID-positive individuals demonstrated Ct values for N1 that were consistently higher from Direct Lysis compared to Acid-pH. Collectively, this work supports that each of these techniques can be used to screen for SARS-CoV-2 in saliva for a cost-effective screening platform.

Evaluating the liver abscess microbiota of beef cattle during a reduction in tylosin supplementation shows differences according to abscess size and fraction.

Liver abscesses (LA) resulting from bacterial infection in cattle pose a significant global challenge to the beef and dairy industries. Economic losses from liver discounts at slaughter and reduced animal performance drive the need for effective mitigation strategies. Tylosin phosphate supplementation is widely used to reduce LA occurrence, but concerns over antimicrobial overuse emphasize the urgency to explore alternative approaches. Understanding the microbial ecology of LA is crucial to this, and we hypothesized that a reduced timeframe of tylosin delivery would alter LA microbiomes. We conducted 16S rRNA sequencing to assess severe liver abscess bacteriomes in beef cattle supplemented with in-feed tylosin. Our findings revealed that shortening tylosin supplementation did not notably alter microbial communities. Additionally, our findings highlighted the significance of sample processing methods, showing differing communities in bulk purulent material and the capsule-adhered material. Fusobacterium or Bacteroides ASVs dominated LA, alongside probable opportunistic gut pathogens and other microbes. Moreover, we suggest that liver abscess size correlates with microbial community composition. These insights contribute to our understanding of factors impacting liver abscess microbial ecology and will be valuable in identifying antibiotic alternatives. They underscore the importance of exploring varied approaches to address LA while reducing reliance on in-feed antibiotics.

Cultivar was more influential than bacterial strain and other experimental factors in recovery of Escherichia coli O157:H7 populations from inoculated live Romaine lettuce plants.

The varied choice of bacterial strain, plant cultivar, and method used to inoculate, retrieve, and enumerate Escherichia coli O157:H7 from live plants could affect comparability among studies evaluating lettuce-enterobacterial interactions. Cultivar, bacterial strain, incubation time, leaf side inoculated, and sample processing method were assessed for their influence in recovering and quantifying E. coli O157:H7 from live Romaine lettuce. Cultivar exerted the strongest effect on E. coli O157:H7 counts, which held up even when cultivar was considered in interactions with other factors. Recovery from the popularly grown green Romaine "Rio Bravo" was higher than from the red variety "Outredgeous." Other modulating variables were incubation time, strain, and leaf side inoculated. Sample processing method was not significant. Incubation for 24 hours post-lettuce inoculation yielded greater counts than 48 hours, but was affected by lettuce cultivar, bacterial strain, and leaf side inoculated. Higher counts obtained for strain EDL933 compared to a lettuce outbreak strain 2705C emphasized the importance of selecting relevant strains for the system being studied. Inoculating the abaxial side of leaves gave higher counts than adaxial surface inoculation, although this factor interacted with strain and incubation period. Our findings highlight the importance of studying interactions between appropriate bacterial strains and plant cultivars for more relevant research results, and of standardizing inoculation and incubation procedures. The strong effect of cultivar exerted on the E. coli O157:H7-lettuce association supports the need to start reporting cultivar information for illness outbreaks to facilitate the identification and study of plant traits that impact food safety risk.IMPORTANCEThe contamination of Romaine lettuce with Escherichia coli O157:H7 has been linked to multiple foodborne disease outbreaks, but variability in the methods used to evaluate E. coli O157:H7 association with live lettuce plants complicates the comparability of different studies. In this study, various experimental variables and sample processing methods for recovering and quantifying E. coli O157:H7 from live Romaine lettuce were assessed. Cultivar was found to exert the strongest influence on E. coli O157:H7 retrieval from lettuce. Other modulating factors were bacterial incubation time on plants, strain, and leaf side inoculated, while sample processing method had no impact. Our findings highlight the importance of selecting relevant cultivars and strains, and of standardizing inoculation and incubation procedures, in these types of assessments. Moreover, results support the need to start reporting cultivars implicated in foodborne illness outbreaks to facilitate the identification and study of plant traits that impact food safety risk.

Improved Canker Processing and Viability Droplet Digital PCR Allow Detection of Erwinia amylovora Viable Nonculturable Cells in Apple Bark.

The bacterium Erwinia amylovora causes fire blight and continues to threaten global commercial apple and pear production. Conventional microbiology techniques cannot accurately determine the presence of live pathogen cells in fire blight cankers. Several factors may prevent E. amylovora from growing on solid culture media, including competing microbiota and the release of bacterial-growth-inhibitory compounds by plant material during sample processing. We previously developed a canker processing methodology and a chip-based viability digital PCR (v-dPCR) assay using propidium monoazide (PMA) to bypass these obstacles. However, sample analysis was still time-consuming and physically demanding. In this work, we improved the previous protocol using an automatic tissue homogenizer and transferred the chip-based v-dPCR to the BioRad QX200 droplet dPCR (ddPCR) platform. The improved sample processing method allowed the simultaneous, fast, and effortless processing of up to six samples. Moreover, the transferred v-ddPCR protocol was compatible with the same PMA treatment and showed a similar dynamic range, from 7.2 × 102 to 7.6 × 107 cells mL-1, as the previous v-dPCR. Finally, the improved protocol allowed, for the first time, the detection of E. amylovora viable but nonculturable (VBNC) cells in cankers and bark tissues surrounding cankers. Our v-ddPCR assay will enable new ways to evaluate resistant pome fruit tree germplasm, further dissect the E. amylovora life cycle, and elucidate E. amylovora physiology, epidemiology, and new options for canker management.

An integrated method for targeted Oxford Nanopore sequencing and automated bioinformatics for the simultaneous detection of bacteria, fungi, and ARG.

The use of metagenomics for pathogen identification in clinical practice has been limited. Here we describe a workflow to encourage the clinical utility and potential of NGS for the screening of bacteria, fungi, and antimicrobial resistance genes (ARGs). The method includes target enrichment, long-read sequencing, and automated bioinformatics. Evaluation of several tools and databases was undertaken across standard organisms (n=12), clinical isolates (n=114), and blood samples from patients with suspected bloodstream infections (n=33). The strategy used could offset the presence of host background DNA, error rates of long-read sequencing, and provide accurate and reproducible detection of pathogens. Eleven targets could be successfully tested in a single assay. Organisms could be confidently identified considering≥60% of best hits of a BLAST-based threshold of e-value 0.001 and a percent identity of>80%. For ARGs, reads with percent identity of>90% and>60% overlap of the complete gene could be confidently annotated. A kappa of 0.83 was observed compared to standard diagnostic methods. Thus, a workflow for the direct-from-sample, on-site sequencing combined with automated genomics was demonstrated to be reproducible. NGS-based technologies overcome several limitations of current day diagnostics. Highly sensitive and comprehensive methods of pathogen screening are the need of the hour. We developed a framework for reliable, on-site, screening of pathogens.

Evaluation of a novel lysis-based sample processing method to optimize Vibrio vulnificus detecting by loop-mediated isothermal amplification assay

BackgroundVibrio vulnificus exists as one of the most serious foodborne pathogens for humans, and rapid and sensitive detection methods are needed to control its infections. As an emerging method, The Loop-Mediated Isothermal Amplification (LAMP) assay has been applied to the early detection of various foodborne pathogens due to its high efficiency, but sample preprocessing still prolongs the complete detection. To optimize the detection process, our study established a novel sample preprocessing method that was more efficient compared to common methods.ResultUsing V. vulnificus as the detecting pathogen, the water-lysis-based detecting LAMP method shortened the preprocessing time to ≤ 1 min with 100% LAMP specificity; the detection limits of the LAMP assay were decreased to 1.20 × 102 CFU/mL and 1.47 × 103 CFU/g in pure culture and in oyster, respectively. Furthermore, the 100% LAMP specificity and high sensitivity of the water-lysis method were also obtained on detecting V. parahaemolyticus, V. alginolyticus, and P. mirabilis, revealing its excellent LAMP adaption with improvement in sensitivity and efficiency.ConclusionOur study provided a novel LAMP preprocessing method that was more efficient compared to common methods and possessed the practical potential for LAMP application in the future.

Sample Processing and Concentration Methods for Viruses from Foods and the Environment Prior to Detection.

Viruses are the leading cause of foodborne illness globally. Concentration of viruses from samples is important for detection because viral contamination of foods often occurs at low levels. In general, virus concentration methods can be classified as either nonspecific, exploiting the relatively homogeneous physicochemical properties of the virus to separate/concentrate it from the sample matrix, or specific, relying on recognition elements such as antibodies to specifically capture and separate viruses from foods. Numerous nonspecific and specific techniques for virus concentration have been reported, each with its own advantages and limitations. Factors to consider can include reagent and equipment costs, time-to-result, ease of use, and potential to eliminate matrix-associated inhibitors. The purpose of this review is to survey the different foodborne virus concentration techniques and their efficacy in various food and environmental matrices as well as discuss some emerging techniques for purification and concentration of viral pathogens from food samples.

Characterization of soy curd residue and full-fat soy flour as protein-based food ingredients

The study investigated the soy curd residue and full-fat soy flour as potential protein-based food ingredients. Standard protocols were used to determine proximate parameters, functional properties, markers of oxidative stability under shelf storage, colour (CIE L* a* b*), and microbial quality of the flours. Commercial Afayak soybean varieties were used to prepare soy curd residue flour and two differently treated soy flours, namely full-fat soy flour and cold-water extracted full-fat soy flour. Findings from the study indicate that processing treatment and storage time significantly (p&lt;0.001) affected the parameters measured. Cold-water extraction of full-fat soy flour resulted in a significantly (p&lt;0.001) higher protein content denoting 1.0, and 1.2-fold than full-fat soy flour and soy curd residue, respectively. Full-fat soy flour showed the highest peroxide, acid, and p-anisidine (p &lt; 0.001) under processing and storage conditions. Soy curd residue was the most oxidatively stable among the samples; however, it was noted that cold-water extraction of full-fat soy had better oxidative stability than full-fat Soy flour. After 12 weeks of storage, peroxide and acid values were below the acceptable limit of 10 mEq/Kg and 0.6 mg/KOH/g, respectively. The study supports the hypothesis that the proximate composition, physicochemical properties, and oxidative stability of soy-based flours are affected by the sample processing method and storage time. The study concludes that the samples characterized in this study are oxidatively stable, protein and energy-rich and may be ideal ingredients for food product development with desirable functional properties.

An omics review and perspective of researches on intrahepatic cholestasis of pregnancy.

Intrahepatic cholestasis of pregnancy (ICP) is one of the common pregnancy complications that may threaten the health of both pregnant women and their fetuses. Hence, it is of vital importance to identify key moleculars and the associated functional pathways of ICP, which will help us to better understand the pathological mechanisms as well as to develop precise clinical biomarkers. The emerging and developing of multiple omics approaches enable comprehensive studies of the genome, transcriptome, proteome and metabolome of clinical samples. The present review collected and summarized the omics based studies of ICP, aiming to provide an overview of the current progress, limitations and future directions. Briefly, these studies covered a broad range of research contents by the comparing of different experimental groups including ICP patients, ICP subtypes, ICP fetuses, ICP models and other complications. Correspondingly, the studied samples contain various types of clinical samples, in vitro cultured tissues, cell lines and the samples from animal models. According to the main research objectives, we further categorized these studies into two groups: pathogenesis and diagnosis analyses. The pathogenesis studies identified tens of functional pathways that may represent the key regulatory events for the occurrence, progression, treatment and fetal effects of ICP. On the other hand, the diagnosis studies tested more than 40 potential models for the early-prediction, diagnosis, grading, prognosis or differential diagnosis of ICP. Apart from these achievements, we also evaluated the limitations of current studies, and emphasized that many aspects of clinical characteristics, sample processing, and analytical method can greatly affect the reliability and repeatability of omics results. Finally, we also pointed out several new directions for the omics based analyses of ICP and other perinatal associated conditions in the future.

Research on the stability changes in expert consensus of the ACTH detection preprocessing scheme

Abstract Objectives Adrenocorticotropic hormone (ACTH) is extremely unstable and can easily degrade at room temperature. The experts agreed that the samples should be transported in an ice bath. If it cannot be detected immediately, the plasma should be separated and frozen, which is difficult to carry out in routine practice. This study was performed to explore the preanalytical factors that influence the stability of adrenocorticotrophic hormone (ACTH) measurements. Methods ACTH levels in 21 EDTA whole-blood samples were measured immediately after 0 h and then divided into three equal groups according to the corresponding values (low, L; median, M; and high, H). Next, three sample processing methods (including seven subtypes) were used: whole blood was uncentrifuged (named the A method), stored at 4 °C or 22 °C, centrifuged but not subjected to plasma removal (the B method), stored at 4 °C or 22 °C, and centrifuged with the plasma removed and stored (the C method) at 4 °C, 22 °C, and −20 °C. Each subtype contained three samples, namely, L, M, and H; these samples were retested using a Siemens XP2000 at different times. The change bias was calculated at 0 h. Results Compared to that at 0 h, there was no significant change in ACTH up to 24 h when the sample was stored at 4 °C or 22 °C with the B method (p&gt;0.05), while it significantly changed (up or down &gt;10 %) at 4 °C/24 h (bias is expressed as the mean±SEM; 13.37±21 %, p&lt;0.05) and 22 °C/12 h (9.13±7.68 %, p&lt;0.05) with the A method; and 4 °C/24 h (8.93±5.54 %, p&lt;0.05), 22 °C/12 h (9.5±4.47 %, p&lt;0.05) and −20 °C/3 h (12.03±4.8 %, p&lt;0.05) with the C method. Conclusions After ACTH samples were centrifuged, the presence of plasma without removal did not affect the detection value, and the sample was stored at 4 °C for up to 24 h. There was a significant difference in the detection of ATCH when the sample was stored at −20 °C and thawed again (p&lt;0.05).

Rapid thermal annealing of chalcogenide thin films for mid-infrared sensing and nonlinear photonics

The influence of rapid thermal annealing (RTA) onto chalcogenide Ge-Sb-Se thin films is reported, focusing on changes in optical properties. These materials possess broad mid-infrared transparency covering the most critical absorption bands for (bio)chemical sensing and high third-order optical nonlinearities for potential applications in nonlinear photonics. The parameters of the RTA process within this study include the annealing temperature, heating rate, and the two sample processing methods – one by placing the sample inside the graphite susceptor and the other by simply laying the sample onto the silicon wafer. Selenide thin films were found to undergo a shift of the absorption edge upon the RTA, resulting in an optical bandgap energy increase (bleaching effect) and a notable refractive index decrease. As a result of structural relaxation, such changes show a great potential of RTA in fine-tuning of optical performance of chalcogenide thin films and planar chalcogenide waveguides. The authors acknowledge the IBAIA (101092723) Horizon Europe project, the ANR AQUAE (ANR-21-CE04-0011-04) project of the French National Research Agency (ANR), and project No. 22-05179S of the Czech Science Foundation (GAČR) for financial support.

Development of selective method for mebeverine detection in blood

To develop the method of biological fluids' sample processing and mebeverine detection to exclude false results' receiving when diagnosing drug intoxication. The study was carried out using «Mebeverine» (NJCO «North star», Russia) medicine and hydrolysis by enzymes, namely papain, chymotrypsin, trypsin, chymopsin and hyaluronidase, was applied for sample processing. The extractions were analyzed by methods of HPLC-MS/MS on Nexera XR modular liquid chromatograph with LCMS-8050 (Shimadzu) tandem mass spectrometer and GC-MS on gas chromatograph connected with QP-2020 (Shimadzu, Japanese) mono quadrupole mass spectrometer. It has been revealed that using selective method of sample processing, which consists of aqueous phase extraction at pH=2-4 and enzymatic hydrolysis by papain and hyaluronidase during isolation from blood, is required to detect mebeverine in biological liquids. It has been proven that the native mebeverine is hydrolyzed to veratric (3.4-dimethoxybenzoic) acid and mebeverine alcohol at alkalotic pH value of medium. It has been shown that mebeverine extraction is necessary to study using HPLC-MS/MS, which will allow to avoid the native mebeverine degradation in chromatograph injector as with GC-MS method analysis.

Research on Video Sample Collection and Processing Methods Based on Artificial Intelligence Platform

Research on Video Sample Collection and Processing Methods Based on Artificial Intelligence Platform