Quantification Of Acids Research Articles

HPTLC Phytochemical Profiling and Simultaneous Quantification of Quercetin and Gallic in Prosopis juliflora (Sw.)

Prosopis juliflora (Sw.) commonly known as jangli babool or vilayati babool have several bioactive compounds of therapeutic needs. The presence of various bioactive compounds and markers specifically, quercetin and gallic acid in the methanolic extract of Prosopis juliflora (fruiting aerial part) denotes their valuable pharmacological activities. Therefore, high performance thin layer chromatography (HPTLC) analysis with simultaneous quantification of quercetin and gallic acid was done for their phytochemical profiling.The phytochemical profiling and simultaneous quantification of quercetin and gallic acid of methanolic extract of Prosopis juliflora through CAMAG HPTLC analysis was determined and results were obtained in the form of chromatogram scanned at the wavelength 254nm and 366nm. Phytochemical profiling of the plant was presented in the tables showing the number of peaks, peak area, area percentage and Rf values. 14 compounds were present in sample 1 and 9 compounds were present in sample 2 denoted by the number of peaks as represented in chromatograms of test samples. Peak area and height were used to quantify quercetin and gallic acid. Quercetin was found to be 1.364% in sample 1 and 0.27% in Sample 2 while gallic acid was 0.088% in sample 1 only. Importance of this research is to rationalize the therapeutic properties of Prosopis juliflora in the indian traditional medicinal system and phytochemical profiling and simultaneous quantification of quercetin and gallic acid reveals that Prosopis juliflora have several bioactive compounds and this might be accountable for their future application in the field of pharmacognostic and pharmacological drug discovery.

Metabolic profiling of pea (Pisum sativum) cultivars in changing environments: Implications for nutritional quality in animal feed

Field pea seeds have long been recognized as valuable feed ingredients for animal diets, due to their high-quality protein and starch digestibility. However, the chemical composition of pea cultivars can vary across different growing locations, consequently impacting their nutrient profiles. This study employs untargeted metabolomics in conjunction with the quantification of fatty acids and amino acids to explore the influence of three different growing locations in Spain (namely Andalusia, Aragon and Asturias), on the nutritional characteristics of seeds of various pea cultivars. Significant interactions between cultivar and environment were observed, with 121 metabolites distinguishing pea profiles. Lipids, lipid-like molecules, phenylpropanoids, polyketides, carbohydrates, and amino acids were the most affected metabolites. Fatty acid profiles varied across locations, with higher C16:0, C18:0, and 18:1 n-9 concentration in Aragón, while C18:2 n-6 predominated in Asturias and C18:3 n-3 in Andalusia. Amino acid content was also location-dependent, with higher levels in Asturias. These findings underscore the impact of environmental factors on pea metabolite profiles and emphasize the importance of selecting pea cultivars based on specific locations and animal requirements. Enhanced collaboration between research and industry is crucial for optimizing pea cultivation for animal feed production.

Spectrofluorometric determination of ascorbic acid in the plasma matrix: Exploring correlation with autism spectrum disorder

Ascorbic acid (Vitamin C) is crucial for bodily functions, including collagen synthesis, immune system support and antioxidant defense. Despite autism spectrum disorder's multifactorial nature involving genetic, environmental and neurological factors, robust evidence exploring the association between ascorbic acid and this disorder is notably lacking. This study introduces an innovative spectrofluorometric method to quantify ascorbic acid in the plasma of healthy children and those with autism spectrum disorder. The method relies on the interaction of ascorbic acid with the fluorescent dye propidium iodide. In acidic conditions, propidium iodide undergoes protonation and selectively binds to the negatively charged ascorbic acid forming an ion-pair complex. This complex alters the molecular structure of propidium iodide inducing chemical fluorescence quenching, that can be utilized for ascorbic acid quantification. The developed method undergoes rigorous validation following ICH guidelines, demonstrating a linear relationship within a concentration range of 4–40 μg/mL, with high precision and accuracy metrics. Analysis of real plasma samples from autistic and healthy children reveals clinically and statistically elevated levels of ascorbic acid in those with autism spectrum disorder.

Development and evaluation of an immunoassay for the quantification of N-acetylneuraminic acid (Neu5Ac) in foods and biosamples

N-acetylneuraminic acid is an active ingredient in tonic foods and an important additive in foods and biopharmaceuticals. To address the limitations of existing methods of N-acetylneuraminic acid quantification, we developed an immunoassay based on antibodies induced in hens using artificial antigen, showing high sensitivity and specificity with no cross-reactivity with eight N-acetylneuraminic acid analogues. An IgY-based indirect competitive enzyme-linked immunosorbent assay showed a detection range of 1.14 to 70.08 ng/mL and a limit of detection of 0.57 ng/mL. In spiked samples, recoveries by the indirect competitive enzyme-linked immunosorbent assay ranged from 74.05% to 110.87% compared with HPLC (73.01% to 108.8%). Consistency between the indirect competitive enzyme-linked immunosorbent assay and HPLC was satisfactory (R2 = 0.9736), demonstrating this established immunoassay as a rapid and reliable approach for N-acetylneuraminic acid analysis. The assay described in this study provides an important method for the screening of N-acetylneuraminic acid in biological samples and foodstuffs.

Quantification of amino acids in small volumes of palm sweat samples

This study investigates the significance of quantifying amino acids in minute sweat volumes using high-performance liquid chromatography with fluorescence detection. Sweat, a valuable biofluid for non-invasive health monitoring, provides real-time insights into physiological changes. Amino acids, which are critical for various physiological processes, are key to protein synthesis and cellular regulation. Therefore, analyzing sweat's amino acid profiles can offer insights into metabolic states, exercise-induced stress, and potential biomarkers for health conditions. For sensitive analysis, amino acids were derivatized with 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F), followed by liquid chromatographic separation on an octadecylsilyl column and fluorescence detection. The developed method was validated and applied to human sweat samples, enabling the quantification of 14 amino acids. The most abundant amino acids in the samples were serine, glycine, and alanine, which aligns with prior studies. This method offers a non-invasive and efficient way to screen for diseases by detecting amino acids in sweat, even with minimal sweat volumes. The approach could also be used to analyze other biomolecules in sweat, expanding its potential applications.

Quantification of lactic acid in wines using an amperometric biosensor

The objective of this study was to develop an analytical method that allows for the rapid and cost-effective detection and quantification of lactic acid in wines. The analysis of lactic acid is a time-consuming and costly process in the food industry. Therefore, the use of an enzymatic amperometric sensor that employs lactate oxidase (LacOx) immobilized on an oxygen electrode enabled the determination of lactic acid in wine. This study utilizes a voltage of −500mV and recorded the amperometric signal was obtained during oxygen consumption while lactic acid oxidation occurred in the sensor reactor. The detection time was at 10 s. A positive linear relationship was obtained between oxygen consumed as a function of time (mg O2/L x s−1). The lactic acid concentration ranged from 1 to 7 mM with a coefficient R2 = 0.994. The sensor exhibited good specificity KM = 0.675. The immobilized enzyme retained over 85% activity for 60 days, allowing for the reuse of the previously modified membrane up to 22 times. In comparison to other methods documented in the literature, the results demonstrate a favourable analytical quality. Furthermore, other aspects, such as the low residual formation, also exhibit a positive outcome. The analysis of lactic acid showed good correlation when compared to HPLC methodology, which occupies the same linear range. This validates the use of the sensor as an alternative method for quantifying lactic acid in wine. The value of this study lies in its presentation of a technique that is more straightforward to implement than traditional methods for quantifying lactic acid in grape wines.

Generic Reporter Sets for Colorimetric Multiplex dPCR Demonstrated with 6-Plex SNP Quantification Panels.

Digital PCR (dPCR) is a powerful method for highly sensitive and precise quantification of nucleic acids. However, designing and optimizing new multiplex dPCR assays using target sequence specific probes remains cumbersome, since fluorescent signals must be optimized for every new target panel. As a solution, we established a generic fluorogenic 6-plex reporter set, based on mediator probe technology, that decouples target detection from signal generation. This generic reporter set is compatible with different target panels and thus provides already optimized fluorescence signals from the start of new assay development. Generic reporters showed high population separability in a colorimetric 6-plex mediator probe dPCR, due to their tailored fluorophore and quencher selection. These reporters were further tested using different KRAS, NRAS and BRAF single-nucleotide polymorphisms (SNP), which are frequent point mutation targets in liquid biopsy. We specifically quantified SNP targets in our multiplex approach down to 0.4 copies per microliter (cp/µL) reaction mix, equaling 10 copies per reaction, on a wild-type background of 400 cp/µL for each, equaling 0.1% variant allele frequencies. We also demonstrated the design of an alternative generic reporter set from scratch in order to give detailed step-by-step guidance on how to systematically establish and optimize novel generic reporter sets. Those generic reporter sets can be customized for various digital PCR platforms or target panels with different degrees of multiplexing.

Screening and discrimination of phenolic acids using bimetallic nanozymes based colorimetric sensor array

Phenolic acids exhibit the pharmacological effects of anti-oxidation, antibacterial, and antitumor, whereas excessive consumption of phenolic acids may bring threat to the human health. Herein, a colorimetric sensor array based on bimetallic nanozymes (Au@Pt, Au@Os, and Au@Pd) with high peroxidase-like activity was fabricated for the rapid screening and discrimination of seven phenolic acids (CHA, DHB, PCA, CA, GA, SA, and TBA). Wherein, the obtained Au@Pt, Au@Os, and Au@Pd nanozymes exhibited good peroxidase-like activity compared with their monometallic nanozymes (Pt, Os, and Pd), showing great stability than natural enzyme. Interestingly, phenolic acids could differentially regulate the peroxidase-like activity of Au@Pt, Au@Os, and Au@Pd nanozyme, and that can be converted into colorimetric signals, which can be further interpreted by combining pattern recognition algorithms. The proposed colorimetric sensor array could accomplish the identification of seven phenolic acids at concentrations as low as 0.005–0.01 mM and their multi-component mixtures. Especially, the ability to distinguish between various phenolic acids in real water samples has been used to verify their practical applicability, which was consistent with the traditional instrumental analysis. This study provided a straightforward and effective method for the recognition and quantification of phenolic acids, carving a promising way for nanozymes in environmental monitoring.

Prevalence of Drugs of Abuse and Cognitive Enhancer Consumption Monitored in Grab Samples and Composite Wastewater via Orbitrap Mass Spectrometry Analysis.

Wastewater (WW)-based epidemiology is an approach for the objective surveillance of the consumption of (illicit) drugs in populations. The aims of this study were to monitor drugs of abuse, cognitive enhancers, and their metabolites as biomarkers in influent WW. Data obtained from different sampling points and mean daily loads were compared with previously published data. The prevalence of analytes was monitored in WW grab samples collected monthly over 22 months at two sampling points and 24 h composite WW samples collected over 2 weeks at a WW treatment plant in the same city. Quantification was performed using a previously validated and published method based on solid-phase extraction followed by liquid chromatography coupled with high-resolution tandem mass spectrometry. Grab samples allowed for frequent detection of ritalinic acid and sporadic detection of drugs of abuse. The daily mean loads calculated for 24 h WW composite samples were in accordance with data published in an international study. Furthermore, loads of amphetamine and methamphetamine increased compared with those observed in a previously published study from 2014. This study showed frequent quantification of ritalinic acid in the grab samples, while drugs of abuse were commonly quantified in the composite WW samples. Daily mean loads were in accordance with trends reported for Germany.

Metal-Organic Framework Based on Ratiometric dual-Fluorescent Sensor Using for Accurate Quantification and on-Site Visual Detection of Ascorbic Acid.

Ascorbic acid is very important to the metabolic process of the body, but excessive intake can lead to diarrhea, kidney calculi and stomach cramps. However, complicated production procedures and harsh experimental settings limit many detection methods, and a simpler and more accurate measurement method is needed. In this study, a smartphone-assisted ratiometric fluorescence sensor was developed for the portable analysis of ascorbic acid. Leveraging the catalytic properties of MIL-53(Fe) to expedite the conversion of H2O2 into hydroxyl radicals, thereby facilitating the oxidation of o-phenylenediamine and terephthalic acid bridging ligand. The sensor showcased exceptional sensitivity in detecting ascorbic acid within a linear range of 0.3-100 µM, boasting an impressive limit of detection at 0.15 µM. Furthermore, through the utilization of color extraction RGB values captured by smartphones, accurate detection of ascorbic acid was achieved with a detection limit of 0.4 µM. Real fruit samples exhibited robust spiked recovery rates ranging from 91 to 119%, accompanied by relative standard deviations ≤ 4.7%. The MIL-53(Fe) nanozyme-based smartphone-assisted ratiometric fluorescence sensor offers an ascorbic acid fluorescence detection device that is visible, accurate, sensitive, and reasonably priced.

Novel Conductive and Redox-Active Molecularly Imprinted Polymer for Direct Quantification of Perfluorooctanoic Acid.

This study developed a novel molecularly imprinted polymer (MIP) that is both conductive and redox-active for directly quantifying perfluorooctanoic acid (PFOA) electrochemically. We synthesized the monomer 3,4-ethylenedioxythiophene-2,2,6,6-tetramethylpiperidinyloxy (EDOT-TEMPO) for electropolymerization on a glassy carbon electrode using PFOA as a template, which was abbreviated as PEDOT-TEMPO-MIP. The redox-active MIP eliminated the need for external redox probes. When exposed to PFOA, both anodic and cathodic peaks of MIP showed a decreased current density. This observation can be explained by the formation of a charge-assisted hydrogen bond between the anionic PFOA and MIP's redox-active moieties (TEMPO) that hinder the conversion between the oxidized and reduced forms of TEMPO. The extent of the current density decrease showed excellent linearity with PFOA concentrations, with a method detection limit of 0.28 ng·L-1. PEDOT-TEMPO-MIP also exhibited high selectivity toward PFOA against other per- and polyfluoroalkyl substances (PFAS) at environmentally relevant concentrations. Our results suggest electropolymerization of MIPs was highly reproducible, with a relative standard deviation of 5.1% among three separate MIP electrodes. PEDOT-TEMPO-MIP can also be repeatedly used with good stability and reproducibility for PFOA detection. This study provides an innovative platform for rapid PFAS quantification using redox-active MIPs, laying the groundwork for developing compact PFAS sensors.

Drop-by-Drop Addition of Reagents to a Double Emulsion.

Developments in droplet microfluidics have facilitated an era of high-throughput, sensitive single-cell, or single-molecule measurements capable of tackling the heterogeneity present in biological systems. Relying on single emulsion (SE) compartments, droplet assays achieve absolute quantification of nucleic acids, massively parallel single-cell profiling, and more. Double emulsions (DEs) have seen recent interest for their potential to build upon SE techniques. DEs are compatible with flow cytometry enabling high-throughput multi-parameter drop screening and eliminate content mixing due to coalescence during lengthy workflows. Despite these strengths, DEs lack important technical functions that exist in SEs such as methods for adding reagents to droplets on demand. Consequently, DEs cannot be used for multistep workflows which has limited their adoption in assay development. Here, strategies to enable reagent addition and other active manipulations on DEs are reported by converting DE inputs to SEs on chip. After conversion, drops are manipulated using existing SE techniques, including reagent addition, before reforming a DE at the outlet. Device designs and operation conditions achieving drop-by-drop reagent addition to DEs are identified and used as part of a multi-step aptamer screening assay performed entirely in DE drops. This work enables the further development of multistep DE droplet assays.

LC-MS analysis of chiral amino acids in human urine reveals D-amino acids as potential biomarkers for colorectal cancer

Colorectal cancer (CRC) is a common malignant tumor in the gastrointestinal tract. Changes in amino acid metabolites have been implicated in tumorigenesis and disease progression. Biomarkers on the basis of chiral amino acids, especially D-amino acids, have not been established for early diagnosis of CRC. Quantification of chiral amino acids, especially very low concentrations of endogenous D-amino acids, is technically challenging. We report here the quantification of L- and D-amino acids in urine samples collected from 115 CRC patients and 155 healthy volunteers, using an improved method. The method of chiral labeling, liquid chromatography, and tandem mass spectrometry enabled separation and detection of 28 amino acids (14 L-amino acids, 13 D-amino acids and Gly). Orthogonal partial least squares discriminant analysis identified 14 targeted variables among these chiral amino acids that distinguished the CRC from the healthy controls. Binary logistic regression analysis revealed that D-α-aminobutyric acid (D-AABA), L-alanine (L-Ala), D-alanine (D-Ala), D-glutamine (D-Gln) and D-serine (D-Ser) could be potential biomarkers for CRC. A receiver operating characteristic curve analysis of combined multi-variables contributed to an area under the curve (AUC) of 0.995 with 98.3 % sensitivity and 96.8 % specificity. A model constructed with D-AABA, D-Ala, D-Gln, and D-Ser achieved an AUC of 0.988, indicating important contributions of D-amino acids to the association with CRC. Further analysis also demonstrated that the metabolic aberration was associated with age and the development of CRC, D-methionine (D-Met) was decreased in CRC patients with age over 50, and D/L-Gln in patients at stage IV was higher than patients at stage I. This study provides the signature of D-amino acids in urine samples and offers a promising strategy for developing non-invasive diagnosis of CRC.

A DNA-peptide probe coupled mass spectrometry-based method for the detection of LncRNA in hepatocyte and serum samples

Liver cancer, a prominent contributor to cancer-related deaths, necessitates timely identification for successful intervention. In recent years, long non-coding RNAs (lncRNAs) have gained attention as potential biomarkers for liver cancer, and accurate quantification of lncRNA is essential for early diagnosis of liver cancer. However, existing methods for lncRNA detection rely on amplification and labeling techniques, resulting in semi-quantitative or qualitative outcomes. DNA-peptide technology offers a promising alternative. It has successfully translated nucleic acid quantification into peptide quantification, particularly in the context of miRNA analysis. However, the intricate structure of long-chain lncRNAs presents a challenge not encountered with miRNAs, making the design and acquisition of specific DNA-peptide probes for direct quantification more difficult. In this study, a strategy for lncRNA quantification was developed using a DNA-peptide probe coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based quasi-targeted proteomics. The inherent structural complexity of long-chain lncRNAs was overcome by designing DNA-peptide probes based on their unique sequence segments, enabling direct quantification without the need for amplification. Highly upregulated in liver cancer (HULC) was identified as a target lncRNA through bioinformatics analysis using GEO2R online software. Subsequently, the target lncRNA (i.e., HULC), which had been biotinylated and bound to streptavidin agarose beforehand, was hybridized with the probe. Following trypsin digestion, the reporter peptide was released and quantified using LC-MS/MS. Finally, this method was applied to analyze HULC levels in liver cancer cell lines and serum samples, enabling quantitative assessment and early diagnosis. The results demonstrated that liver cancer diagnostics could be enhanced through the integration of mass spectrometry and DNA-peptide probe technology for lncRNA quantification.

Integration of concentration gradient generator with competitive PCR in a droplet for rapid nucleic acid quantification

Competitive PCR is an efficient way for the measurement of nucleic acids without requiring a standard curve. It uses a competitor template mimicking the target sequence for direct comparison and quantification during amplification. However, manually preparing various concentrations for competitive PCR is labor-intensive. Additionally, target and competitor DNA bands are often inadequately separated on gels due to their similar sizes. This leads to inaccurate distinction and imprecise measurement of bandwidths and intensities, resulting in high standard deviations in quantification. Thus, this study presents an alternative way to combine droplet competitive PCR with the concentration gradient generator in a microfluidic device that simplifies competitive PCR preparation and provides precise control over reaction conditions and sample handling. Generating a wide range of competitor-to-target ratios in a single experiment enhances statistical reliability and isolating individual reactions in droplets reduces background noise and increases sensitivity. Additionally, it eliminates gel electrophoresis, improves consistency and reproducibility, requires smaller sample and reagent volumes, and allows direct sample quantification through a calibration curve for fast, simple quantification. We envision that our platform can offer a promising alternative to digital PCR, addressing its challenges and driving progress in molecular biology and diagnostics.

A new RP-HPLC method for the simultaneous detection and quantification of minocycline and ascorbic acid in pure forms and combined pharmaceutical dosage forms

We report the first reverse-phase, high performance liquid chromatography (RP-HPLC) method for the rapid and simple simultaneous detection and quantification of minocycline and ascorbic acid in raw and pharmaceutical dosage forms. Detection was performed on a Sunniest C-18 column (5 μm particle size, 150 mm × 4.6 m mi.d(, at UV wavelength of 255 nm. The mobile phase consisted of potassium dihydrogen phosphate pH 2.8: Acetonitrile: Methanol (85:10:5), with 0.6 v/v% TEA and adjusted with orthophosphoric acid to a pH of 2.8 in an isocratic elution mode, with a flow rate of 0.8 mL/min. Performed analysis on the method proved that the newly developed method was sensitive, selective, accurate, precise, and robust. The method demonstrated good linearity with r2 = 0.9999 (n = 7) for both drugs and was validated in the sample concentration ranges of 1–100 and 5–500 µg mL−1 for minocycline and ascorbic acid, respectively. Both intra- and inter-day precisions were less than 2 % for both drugs, with limits of detection of 1.59 and 7.89 µg/mL and limits of quantification of 4.83 and 23.89 µg/mL, for minocycline and ascorbic acid, respectively. The applicability of the method was demonstrated by accurately determining the drug content of two commercial pharmaceutical formulations.

Bacteroides uniformis Ameliorates Carbohydrate and Lipid Metabolism Disorders in Diabetic Mice by Regulating Bile Acid Metabolism via the Gut-Liver Axis.

Type 2 diabetes mellitus (T2DM) is a metabolic syndrome characterized by chronic inflammation, insulin resistance, and islet cell damage. The prevention of T2DM and its associated complications is an urgent public health issue that affects hundreds of millions of people globally. Numerous studies suggest that disturbances in gut metabolites are important driving forces for the pathogenesis of diabetes. However, the functions and mechanisms of action of most commensal bacteria in T2DM remain largely unknown. The quantification of bile acids (BAs) in fecal samples was performed using ultra-performance liquid chromatography-tandem mass spectrometer (UPLC-MS/MS). The anti-diabetic effects of Bacteroides uniformis (B. uniformis) and its metabolites cholic acid (CA) and chenodeoxycholic acid (CDCA) were assessed in T2DM mice induced by streptozocin (STZ) plus high-fat diet (HFD). We found that the abundance of B. uniformis in the feces and the contents of CA and CDCA were significantly downregulated in T2DM mice. B. uniformis was diminished in diabetic individuals and this bacterium was sufficient to promote the production of BAs. Colonization of B. uniformis and intragastric gavage of CA and CDCA effectively improved the disorder of glucose and lipid metabolism in T2DM mice by inhibiting gluconeogenesis and lipolysis in the liver. CA and CDCA improved hepatic glucose and lipid metabolism by acting on the Takeda G protein-coupled receptor 5 (TGR5)/adenosine monophosphate-activated protein kinase (AMPK) signaling pathway since knockdown of TGR5 minimized the benefit of CA and CDCA. Furthermore, we screened a natural product-vaccarin (VAC)-that exhibited anti-diabetic effects by promoting the growth of B. uniformis in vitro and in vivo. Gut microbiota pre-depletion abolished the favorable effects of VAC in diabetic mice. These data suggest that supplementation of B. uniformis may be a promising avenue to ameliorate T2DM by linking the gut and liver.

Quantification of Glycyrrhizic Acid in FLEGMEN-SIP Capsules Using High-Performance Liquid Chromatography for CNS Disorders

Background: Neurological diseases affect over one billion people globally, presenting a significant health burden, especially for vulnerable populations. The FLEGMEN-SIP capsule was developed as a treatment option for central nervous system disorders, containing glycyrrhizic acid as its primary active ingredient. This study aims to quantify the glycyrrhizic acid content in FLEGMEN-SIP capsules using high-performance liquid chromatography (HPLC) to ensure compliance with therapeutic standards. Methods: The study utilized HPLC to quantify glycyrrhizic acid in FLEGMEN-SIP capsules. The capsules contain a dry extract derived from Phlomis regelii, Leonurus turkestanicus, Mentha piperita, and Glycyrrhiza glabra, with glycyrrhizic acid comprising 1.39% of the dry extract. Samples were prepared by dissolving 0.050 g of the drug in the mobile phase and filtered using a 0.45 µm membrane filter. The HPLC system included a Zorbax column and UV detection at 254 nm. The analysis was repeated five times for accuracy. Results: The glycyrrhizic acid content in FLEGMEN-SIP capsules was determined to be 0.55%, surpassing the minimum regulatory requirement of 0.4%. The chromatographic method demonstrated high reproducibility and reliability, confirming the quality and therapeutic efficacy of the capsules. Conclusion: The study validated the use of HPLC as an effective method for quantifying glycyrrhizic acid in FLEGMEN-SIP capsules. The results confirm the capsules meet regulatory standards, ensuring their suitability for treating central nervous system disorders.

Gold nanostructures on polyelectrolyte-brush-modified cellulose membranes as a synergistic platform for uric acid detection

In this study, we present a convenient approach utilizing gold nanostructures coated cellulose membrane for the quantification of uric acid in an aqueous solution. The synthesis of system was achieved by functionalizing cellulose membrane with poly[2-(methacryloyloxy)ethyl]trimethylammonium chloride (PMETAC) and cross-linked with ethylene glycol dimethacrylate (EGDMA). FT-IR and XPS confirm the formation of PMETAC and PMETAC/EGDMA on the cellulose. The fabricated substrates were exposed to tetrachloroaurate solution, then reduced by NaBH4. We have systematically investigated the catalytic oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) by hydrogen peroxide (H2O2) in various pH conditions, absent uric acid, using the fabricated substrates. The colorimetric response—observed through UV–Vis spectroscopy—revealed significant shifts in absorbance at 660 nm, correlating with uric acid concentrations across a range of pH levels. The films exhibited a pronounced color change from green to light yellow in basic to neutral environments and from yellow to dark green under more acidic conditions, demonstrating their potential for high-sensitivity uric acid detection. The assessment of the catalytic films' reusability and stability revealed insights into their enduring performance, identifying opportunities for enhancing material design and functionality for extended applications. This study not only underscores the films' versatile detection capabilities but also emphasizes the importance of pH in tuning the assay's sensitivity and specificity.

Advancing Pathogen Identification: The Role of Digital PCR in Enhancing Diagnostic Power in Different Settings.

Digital polymerase chain reaction (dPCR) has emerged as a groundbreaking technology in molecular biology and diagnostics, offering exceptional precision and sensitivity in nucleic acid detection and quantification. This review highlights the core principles and transformative potential of dPCR, particularly in infectious disease diagnostics and environmental surveillance. Emphasizing its evolution from traditional PCR, dPCR provides accurate absolute quantification of target nucleic acids through advanced partitioning techniques. The review addresses the significant impact of dPCR in sepsis diagnosis and management, showcasing its superior sensitivity and specificity in early pathogen detection and identification of drug-resistant genes. Despite its advantages, challenges such as optimization of experimental conditions, standardization of data analysis workflows, and high costs are discussed. Furthermore, we compare various commercially available dPCR platforms, detailing their features and applications in clinical and research settings. Additionally, the review explores dPCR's role in water microbiology, particularly in wastewater surveillance and monitoring of waterborne pathogens, underscoring its importance in public health protection. In conclusion, future prospects of dPCR, including methodological optimization, integration with innovative technologies, and expansion into new sectors like metagenomics, are explored.