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AbstractAn overview of the latest advances in the design of electrochemical sensor architectures dedicated to the determination of drugs from the statin class is presented in this review. Statins are drugs widely consumed for cholesterol control, and their determination in different matrices through the application of electroanalysis is growing considering advantages such as operational simplicity, lower cost and ease of sample preparation. Within the context of statins, electrochemical sensor architectures can be subdivided into conventional/classical electrodes such as glassy carbon electrodes, carbon paste electrodes, pencil graphite electrodes, boron-doped diamond electrodes and metallic electrodes, and more modern electrode systems, including the screen-printed electrodes and 3D-printed electrodes. Thus, different aspects related to the preparation of these electrochemical sensors and analytical performance are presented, also reflecting advances in terms of designs of new architectures and possible improvements not previously reviewed. Analyzed samples, advantages and disadvantages of different implemented sensor’s modification strategies and perspectives for the electroanalysis of statins are also included throughout the work. [ABSTRACT FROM AUTHOR]

COVID-19, a novel coronavirus, was identified as the primary source of pneumonia and severe acute respiratory syndrome. Roflumilast (ROF) is a widely used anti-inflammatory medication for controlling severe inflammatory pulmonary conditions. A novel sensor of sodium polystyrene sulfonate has been constructed to get an economic modifier for developing sensitive and swift voltammetric determination of ROF by square wave voltammetry in pharmaceutical dosage form and biological fluid. For obtaining best results, a universal buffer was used at pH=7. The calibration range was found to be 30×10-9 - 3×10-4 M and the correlation coefficient was computed to be 0.9995, under optimum conditions, while LOD and LOQ were found to be 9×10-9, 27×10-9 M respectively. Sensitive simultaneous determination of ROF and Salmeterol (SAL), the co-administered drug, was achieved efficiently by the sodium polystyrene sulfonate sensor. The modified electrode was proved to be the method of choice for analysis of ROF in the dosage forms and in human biological fluids due to high sensitivity, good accuracy, and specificity. Both the number of transported electrons and the potential for an electro-oxidation pathway were examined. Greenness assessment of the presented method was checked by applying NEMI, ESA, and GAPI tools and the method proved to be acceptably green. [ABSTRACT FROM AUTHOR]

Redox metabolism is an integral part of the glutathione system, encompassing reduced and oxidized glutathione, hydrogen peroxide, and associated enzymes. This core process orchestrates a network of thiol antioxidants like thioredoxins and peroxiredoxins, alongside critical thiol-containing proteins such as mercaptoalbumin. Modifications to thiol-containing proteins, including oxidation and glutathionylation, regulate cellular signaling influencing gene activities in inflammation and carcinogenesis. Analyzing thiol antioxidants, especially glutathione, in biological fluids offers insights into pathological conditions. This review discusses the analytical methods for biothiol determination, mainly in blood plasma. The study includes all key methodological aspects of spectroscopy, chromatography, electrochemistry, and mass spectrometry, highlighting their principles, benefits, limitations, and recent advancements that were not included in previously published reviews. Sample preparation and factors affecting thiol antioxidant measurements are discussed. The review reveals that the choice of analytical procedures should be based on the specific requirements of the research. Spectrophotometric methods are simple and cost-effective but may need more specificity. Chromatographic techniques have excellent separation capabilities but require longer analysis times. Electrochemical methods enable real-time monitoring but have disadvantages such as interference. Mass spectrometry-based approaches have high sensitivity and selectivity but require sophisticated instrumentation. Combining multiple techniques can provide comprehensive information on thiol antioxidant levels in biological fluids, enabling clearer insights into their roles in health and disease. This review covers the time span from 2010 to mid-2024, and the data were obtained from the SciFinder® (ACS), Google Scholar (Google), PubMed®, and ScienceDirect (Scopus) databases through a combination search approach using keywords. [ABSTRACT FROM AUTHOR]

This study showcases the successful development of a hybrid reduced graphene oxide-metal organic framework modified glassy carbon electrode (rGO-MOFs/GCE) electrochemical biosensor for the detection of synthetic testosterone (TST) as a performance-enhancing drug in athletes. The results demonstrate a linear relationship between the voltametric responses and the testosterone concentration, indicating the sensor's effectiveness in measuring TST. Furthermore, the sensor's performance in detecting TST in real human serum samples from athletes was also validated. The sensor's linear range and detection limit are comparable, if not superior, to those of other recently developed electrochemical sensors, positioning it as a promising tool for TST detection. Additionally, the method's selectivity was assessed and found to be unaffected by substances typically present in biological fluids and food samples, further affirming the sensor's reliability. The application of the rGO/MOF/GCE sensor to detecting and quantifying TST in actual human serum samples yielded favorable results. The synergistic effects of rGO and MOF, which improve the electrical conductivity and biocompatibility of MOF and the porosity and catalytic activity of rGO, are responsible for the sensor's enhanced performance in terms of sensitivity, selectivity, stability, and response time. These findings underscore the potential of the rGO/MOF/GCE sensor platform for various biomedical applications.

This study showcases the successful development of a hybrid reduced graphene oxide-metal organic framework modified glassy carbon electrode (rGO-MOFs/GCE) electrochemical biosensor for the detection of synthetic testosterone (TST) as a performance-enhancing drug in athletes. The results demonstrate a linear relationship between the voltametric responses and the testosterone concentration, indicating the sensor's effectiveness in measuring TST. Furthermore, the sensor's performance in detecting TST in real human serum samples from athletes was also validated. The sensor's linear range and detection limit are comparable, if not superior, to those of other recently developed electrochemical sensors, positioning it as a promising tool for TST detection. Additionally, the method's selectivity was assessed and found to be unaffected by substances typically present in biological fluids and food samples, further affirming the sensor's reliability. The application of the rGO/MOF/GCE sensor to detecting and quantifying TST in actual human serum samples yielded favorable results. The synergistic effects of rGO and MOF, which improve the electrical conductivity and biocompatibility of MOF and the porosity and catalytic activity of rGO, are responsible for the sensor's enhanced performance in terms of sensitivity, selectivity, stability, and response time. These findings underscore the potential of the rGO/MOF/GCE sensor platform for various biomedical applications. [ABSTRACT FROM AUTHOR]

The design, development, and application of a new electrochemical sensor for the detection of lactate in athletes' urine are described in this paper. Reduced graphene oxide (rGO) and poly(amidoamine) (PAMAM) dendritic polymers form the nanocomposite upon which the sensor is built. The PAMAM/rGO nanocomposite, which combines the robust structure and active sites of PAMAM with the high surface area and better conductivity of rGO, improves the sensitivity and selectivity of lactate detection. The sensor demonstrated a broad linear range from 1 to 3200 µM, a high sensitivity of 0.07907 µA/µM, and a detection limit of 0.017 µM. The selectivity of the sensor was deemed sufficient for the detection of lactate at physiologically relevant concentrations in the presence of common interfering chemicals. Furthermore, the sensor showed good repeatability, reproducibility, and long-term stability; over the course of a month, there was no appreciable decrease in sensitivity. Real sample analysis, where relative standard deviation (RSD) values were less than 4.09% and average recovery rates were above 98.00%, validated the procedure's accuracy and precision. The suitability of the PAMAM/rGO-based sensor for measuring lactate levels in urine samples is demonstrated by these findings, which pave the way for the development of real-time, non-invasive sports nutrition monitoring devices. [ABSTRACT FROM AUTHOR]

In this work, a new electrochemical sensor for the detection of the doping agent metoprolol (MTP) in food samples and bodily fluids is presented. The sensor's foundation is a nanocomposite made of polypyrrole (PPy) and nickel oxide nanoparticles (NiO NPs) on a glassy carbon electrode (GCE). Pyrole was electropolymerized to create the nanocomposite, and then NiO NPs were electrodedeposited on the GCE surface (NiO NPs/PPy/GCE). By combining the benefits of PPy with NiO NPs, this technique offers good electrocatalytic activity and a large surface area for analyte interaction. The nanocomposite was characterized using structural analyses such as scanning electron microscopy (SEM), X-ray diffractometry (XRD) and X-ray photoelectron spectroscopy (XPS). These analyses revealed a network-like structure that improved the accessibility of the electrolyte ions and showed that the nanocomposite had been successfully deposited on the GCE surface. The electrochemical MTP sensor was examined using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) tests. The sensor's sensitivity was 0.03074 μA/μM, and it demonstrated a linear connection between the peak currents and the MTP concentrations (5–1600μM). The suggested sensor's limit of quantification (LOQ) and limit of detection (LOD) were determined to be 0.581 μM and 0.018 μM, respectively. The prepared urine sample produced acceptable recovery rates in the range of 98.40–99.86% in the real sample analyses, together with low relative standard deviation values (below 4.16%). In a similar vein, the prepared apple juice sample analysis revealed low relative standard deviation values (less than 4.28%) and respectable recovery rates ranging from 97.20 to 99.66%. The results showed low relative standard deviation values and good recovery rates, demonstrating the high precision and dependability of the suggested approach. [ABSTRACT FROM AUTHOR]

The goal of this work is to create highly sensitive and selective electrochemical sensors that can detect lactate, an essential substance in the body's anaerobic breakdown of carbohydrates, by utilizing lactate oxidase (LOx) and glutaraldehyde (GA)-modified indium-doped zinc oxide (ZnO) nanorods. Several structural investigations validated the effective immobilization of LOx and GA on the modified glassy carbon electrode (GCE) with indium-doped ZnO nanorods. Lactate was detected with the LOx-GA/In-doped ZnO biosensor, which showed linear range of 0.1–36 mM, sensitivity value of 0.73301 µA/mM, and quantification and detection limits of 2.7 μM and 0.8 μM, respectively. The biosensor also displayed stability, repeatability, and selectivity. The sensor demonstrated remarkable lactate recovery rates when applied to real serum and urine specimens from athletes. The serum samples ranged from 96.00% to 99.28% with a relative standard deviation (RSD%) of 3.77–4.25, and the urine samples from 94.00 to 98.58 with an RSD% of 3.55–4.62. These results point to the LOx-GA/In-doped ZnO/GCE sensor platform's potential for a range of biomedical uses.

The goal of this work is to create highly sensitive and selective electrochemical sensors that can detect lactate, an essential substance in the body's anaerobic breakdown of carbohydrates, by utilizing lactate oxidase (LOx) and glutaraldehyde (GA)-modified indium-doped zinc oxide (ZnO) nanorods. Several structural investigations validated the effective immobilization of LOx and GA on the modified glassy carbon electrode (GCE) with indium-doped ZnO nanorods. Lactate was detected with the LOx-GA/In-doped ZnO biosensor, which showed linear range of 0.1–36 mM, sensitivity value of 0.73301 µA/mM, and quantification and detection limits of 2.7 μM and 0.8 μM, respectively. The biosensor also displayed stability, repeatability, and selectivity. The sensor demonstrated remarkable lactate recovery rates when applied to real serum and urine specimens from athletes. The serum samples ranged from 96.00% to 99.28% with a relative standard deviation (RSD%) of 3.77–4.25, and the urine samples from 94.00 to 98.58 with an RSD% of 3.55–4.62. These results point to the LOx-GA/In-doped ZnO/GCE sensor platform's potential for a range of biomedical uses. [ABSTRACT FROM AUTHOR]

Surface fouling poses a significant challenge that restricts the analytical performance of electrochemical sensors in both in vitro and in vivo applications. Biofouling resistance is paramount to guarantee the reliable operation of electrochemical sensors in complex biofluids (e.g., blood, serum, and urine). Seeking efficient strategies for surface fouling and establishing highly sensitive sensing platforms for applications in complex media have received increasing attention in the past. In this review, we provide a comprehensive overview of recent research efforts focused on antifouling electrochemical sensors. Initially, we present a detailed illustration of the concept about biofouling along with an exploration of four key antifouling mechanisms. Subsequently, we delve into the commonly employed antifouling strategies in the fabrication of electrochemical sensors. These encompass physical surface topography (micro/nanostructure coatings and filtration membranes) and chemical surface modifications (PEG and its derivatives, zwitterionic polymers, peptides, proteins, and various other antifouling materials). The progress in antifouling electrochemical sensors is proposed concerning the antifouling mechanisms as well as sensing capability assessments (e.g., sensitivity, stability, and practical application ability). Finally, we summarize the evolving trends in the field and highlight some key remaining limitations. [ABSTRACT FROM AUTHOR]

Redox metabolism is an integral part of the glutathione system, encompassing reduced and oxidized glutathione, hydrogen peroxide, and associated enzymes. This core process orchestrates a network of thiol antioxidants like thioredoxins and peroxiredoxins, alongside critical thiol-containing proteins such as mercaptoalbumin. Modifications to thiol-containing proteins, including oxidation and glutathionylation, regulate cellular signaling influencing gene activities in inflammation and carcinogenesis. Analyzing thiol antioxidants, especially glutathione, in biological fluids offers insights into pathological conditions. This review discusses the analytical methods for biothiol determination, mainly in blood plasma. The study includes all key methodological aspects of spectroscopy, chromatography, electrochemistry, and mass spectrometry, highlighting their principles, benefits, limitations, and recent advancements that were not included in previously published reviews. Sample preparation and factors affecting thiol antioxidant measurements are discussed. The review reveals that the choice of analytical procedures should be based on the specific requirements of the research. Spectrophotometric methods are simple and cost-effective but may need more specificity. Chromatographic techniques have excellent separation capabilities but require longer analysis times. Electrochemical methods enable real-time monitoring but have disadvantages such as interference. Mass spectrometry-based approaches have high sensitivity and selectivity but require sophisticated instrumentation. Combining multiple techniques can provide comprehensive information on thiol antioxidant levels in biological fluids, enabling clearer insights into their roles in health and disease. This review covers the time span from 2010 to mid-2024, and the data were obtained from the SciFinder® (ACS), Google Scholar (Google), PubMed®, and ScienceDirect (Scopus) databases through a combination search approach using keywords.

This research focused on the electrochemical detection of metoprolol (MTP) in food products and biological fluids using modified electrodes made of graphitic carbon nitride (g-C3N4) and copper phthalocyanine (CuPc) nanostructures for monitoring athlete doping. The g-C3N4/CuPc nanocomposite was successfully prepared, as shown by the findings of SEM, EDX, XRD, and FT-IR studies, and CuPc anchoring rod-like structures are anchored on the g-C3N4 nanosheets. GCE, CuPc/GCE, and g-C3N4/GCE all displayed lower oxidation peaks towards addition MTP, according to electrochemical tests utilizing CV and DPV. The detection limit, sensitivity, and linear range of the sensor were determined to be 10 nM, 0.06783 µA/µM, and 8 to 1760 µM, respectively. The sensor also displayed notable reactivity and selectivity towards MTP. We looked into the capacity of g-C3N4/CuPc/GCE to quantify the amount of MTP in prepared samples made from human serum and apple juice. The outcomes of the analytical evaluations, which used the common addition approach and the DPV as their target, showed how well g-C3N4/CuPc/GCE worked to identify the presence of MTP in biological fluids and food samples. The assays demonstrated strong accuracy, with a relative standard deviation (RSD) of less than 4.63%, and good recoveries ranging from 98.40 to 99.60%. [ABSTRACT FROM AUTHOR]

In forensic sciences, body fluids, or biological traces, are a major source of information, and their identification can play a decisive role in criminal investigations. Currently, the nature of biological fluids is assessed using immunological, physico-chemical, mRNA and epigenetic methods, but these have limits in terms of sensitivity and specificity. The emergence of next-generation sequencing technologies offers new opportunities to identify the nature of body fluids by determining bacterial communities. The aim of this pilot study was to assess whether analysis of the bacterial communities in isolated and mixed biological fluids could reflect the situation observed in real forensics labs. Several samples commonly encountered in forensic sciences were tested from healthy volunteers: saliva, vaginal fluid, blood, semen and skin swabs. These samples were analyzed alone or in combination in a ratio of 1:1. Sequencing was performed on the Ion Gene StudioTM S5 automated sequencer. Fluids tested alone revealed a typical bacterial signature with specific bacterial orders, enabling formal identification of the fluid of interest, despite inter-individual variations. However, in biological fluid mixtures, the predominance of some bacterial microbiomes inhibited interpretation. Oral and vaginal microbiomes were clearly preponderant, and the relative abundance of their bacterial communities and/or the presence of common species between samples made it impossible to detect bacterial orders or genera from other fluids, although they were distinguishable from one another. However, using the beta diversity, salivary fluids were identified and could be distinguished from fluids in combination. While this method of fluid identification is promising, further analyses are required to consolidate the protocol and ensure reliability. [ABSTRACT FROM AUTHOR]

Time-resolved fluorescence anisotropy has been extensively used to detect changes in bimolecular rotation associated with viscosity levels within cells and other solutions. Physiological alterations of the viscosity of biological fluids have been associated with numerous pathological causes. This current work serves as proof of concept for a method to measure viscosity changes in small analyte volumes representative of biological fluids. The fluorophores used in this study were fluorescein disodium salt and Enhanced Green Fluorescent Protein (EGFP). To assess the ability of the method to accurately detect viscosity values in small volume samples, we conducted measurements with 12 µL and 100 µL samples. No statistically significant changes in determined viscosities were recorded as a function of sample volume for either fluorescent probe. The anisotropy of both fluorescence probes was measured in low viscosity standards ranging from 1.02 to 1.31 cP, representative of physiological fluid values, and showed increasing rotational correlation times in response to increasing viscosity. We also showed that smaller fluid volumes can be diluted to accommodate available cuvette volume requirements without a loss in the accuracy of detecting discrete viscosity variations. Moreover, the ability of this technique to detect subtle viscosity changes in complex fluids similar to physiological ones was assessed by using fetal bovine serum (FBS) containing samples. The presence of FBS in the analytes did not alter the viscosity specific rotational correlation time of EGFP, indicating that this probe does not interact with the tested analyte components and is able to accurately reflect sample viscosity. We also showed that freeze–thaw cycles, reflective of the temperature-dependent processes that biological samples of interest could undergo from the time of collection to analyses, did not impact the viscosity measurements' accuracy. Overall, our data highlight the feasibility of using time-resolved fluorescence anisotropy for precise viscosity measurements in biological samples. This finding is relevant as it could potentially expand the use of this technique for in vitro diagnostic systems. [ABSTRACT FROM AUTHOR]

Sunitinib is a tyrosine kinase inhibitor used for the treatment of renal cell carcinoma and gastrointestinal stromal tumors. In this study, two spectroscopic methods, spectrofluorometric and spectrophotometric, were utilized to quantify sunitinib in different matrices. In method I, the native fluorescence of erythrosine B was quenched by forming ion‐pair complex with increasing quantities of sunitinib. This approach was utilized for measuring sunitinib in its dosage forms and spiked plasma. After excitation at 528 nm, the quenching of fluorescence is linearly related to the concentration across the range of 0.05–0.5 μg mL−1 at 550 nm in Britton–Robinson buffer (pH 4.0), with a correlation value of 0.9999 and a high level of sensitivity with detection limit down to 10 ng mL−1. Method II relies on spectrophotometric measurements of the produced complex at 550 nm across a range of 0.5–10.0 μg mL−1, with good correlation value of 0.9999. This method has a detection limit down to 0.16 μg mL−1. The proposed methodologies were validated according to International Conference on Harmonization (ICH) guidelines with satisfactory results. The stoichiometry of the reaction was determined through the application of Job's method, while the mechanism of quenching was investigated by employing the Stern–Volmer plot. The designated methods were used to estimate sunitinib in its capsules and in spiked human plasma. Additionally, the statistical analysis of the data revealed no substantial differences when compared to previous reported spectroscopic method. Green assessment tools provide further details about the eco‐friendly nature of the methods. [ABSTRACT FROM AUTHOR]

For the first time, an analysis was made of the antioxidant properties of conjugates of CeO2 nanoparticles with human serum albumin (CeO2@HSA), including HSA isolated from blood plasma and biological fluids similar in composition to blood plasma, namely, peritoneal (ascitic) and synovial (articular) fluids. The antioxidant activity of hybrid nanomaterials was studied in relation to alkylperoxyl radicals by luminol-dependent chemiluminescence. It was shown that the interaction of CeO2 nanoparticles with purified human serum albumin is accompanied by a decrease in the antioxidant and prooxidant potential of albumin by a factor of ⁓1.5. Presumably, this is caused by the interaction of nanodispersed CeO2 with sulfhydryl groups of the protein. Conjugates of CeO2 nanoparticles with albumin isolated from biological fluids (CeO2@HSA) exhibit a synergistic antioxidant effect. In this case, the mechanism of antioxidant activity is fundamentally different from that for CeO2 sols modified with purified human serum albumin. According to quantitative assessment, the antioxidant capacity of CeO2@HSA conjugates is ⁓20 times lower than that of Trolox, a water-soluble analog of vitamin E. [ABSTRACT FROM AUTHOR]

The freezing of biological fluids is intensively studied but remains elusive as it is affected not only by the various components but also by the crowding nature of the biological fluids. Herein, we constructed spherical crowders, fibrous crowders, and coacervates by various components ranging from surfactants to polymers and proteins, to mimic three typical crowders in biological fluids, i.e. globular proteins, fibrous networks, and condensates of biomolecules. It is elucidated that the three crowders exhibit low, moderate, and strong ice growth inhibition activity, respectively, resulting from their different abilities in slowing down water dynamics. Intriguingly, the coacervate consisting of molecules without obvious ice growth inhibition activity strongly inhibits ice growth, which is firstly employed as a highly‐potent cryoprotectant. This work provides new insights into the survival of freezing‐tolerant organisms and opens an avenue for the design of ice‐controlling materials. [ABSTRACT FROM AUTHOR]

A new green-validated and highly sensitive electrochemical method for the determination of molnupiravir (MOV) has been developed using cyclic voltammetry. The proposed analytical platform involves the use of a disposable laboratory-made screen-printed reduced graphene oxide 2.5% modified electrode (rGO-SPCE 2.5%) for the first time to measure MOV with high specificity. The surface morphology of the sensor was investigated by using a scanning electron microscope armed with an energy-dispersive X-ray probe. The fabricated sensor attained improved sensitivity when sodium dodecyl sulfate (SDS) surfactant (3 µM) was added to the supporting electrolyte solution of 0.04 M Britton–Robinson buffer at pH 2. The electrochemical activity of rGO-SPCE was examined in comparison with two different working electrodes in order to demonstrate that it was the most competitive sensor for MOV monitoring. The method was validated using differential pulse voltammetry according to ICH guidelines, resulting in good precision, accuracy, specificity, and robustness over a concentration range of 0.152–18.272 µM, with a detection limit of 0.048 µM. The stability investigation demonstrated that rGO-SPCE 2.5% can provide high-stability behavior towards the analyte throughout a six-week period under refrigeration. The fabricated rGO-SPCE 2.5% was successfully employed for the measurement of MOV in pharmaceutical capsules and human biofluids without the interference of endogenous matrix components as well as the commonly used excipient. [ABSTRACT FROM AUTHOR]

A simple, fast, sensitive, cost-effective, and well-proven spectrofluorimetric method has been developed for the quantification of cetirizine dihydrochloride (CTZ). The quenching effect of CTZ on the fluorescence intensity of Eosin Y was utilized to generate an ion-pair complex that can be detected at 549 nm using a 301 nm excitation wavelength in the presence of glycine buffer (pH 4.0) for the method development. The factors that influence reactions were thoroughly examined and optimized. With a determination coefficient of 0.9996, the fluorescence quenching value was linear to CTZ concentration in the range of 1–40 µg/mL. The estimated detection and quantification limits were determined to be 0.02 and 0.08 µg/mL, respectively. The method selectivity was validated by analyzing the effects of excipients, and no interference was found. The established approach was applied to determine the presence of CTZ in products available on the market as well as in biological samples. The methodology was validated using guidelines from the International Conference on Harmonization, and percent recoveries for pharmaceutical items varied from 90.6 to 103.5% and for biological fluids from 97.9 to 102.5%. The method has been successfully used for the content uniformity test with high percent recovery and low relative standard deviation. [ABSTRACT FROM AUTHOR]

Capillary electrophoresis is recognized as a valued separation technique for its high separation efficiency, low sample consumption, good economic and ecological aspects, reproducibility, and complementarity to traditional liquid chromatography techniques. Capillary electrophoresis experiments are generally performed utilizing optical detection, such as ultraviolet or fluorescence detectors. However, in order to provide structural information, capillary electrophoresis hyphenated to highly sensitive and selective mass spectrometry has been developed to overcome the limitations of optical detections. Capillary electrophoresis‐mass spectrometry is increasingly popular in protein analysis, including biopharmaceutical and biomedical research. It is frequently applied for the determination of physicochemical and biochemical parameters of proteins, offers excellent performance for in‐depth characterizations of biopharmaceuticals at various levels of analysis, and has been also already proven as a promising tool in biomarker discovery. In this review, we focus on the possibilities and limitations of capillary electrophoresis‐mass spectrometry for protein analysis at their intact level. Various capillary electrophoresis modes and capillary electrophoresis‐mass spectrometry interfaces, as well as approaches to prevent protein adsorption and to enhance sample loading capacity, are discussed and the recent (2018–March 2023) developments and applications in the field of biopharmaceutical and biomedical analysis are summarized. [ABSTRACT FROM AUTHOR]

Mathematical simulation of biological fluids is of upmost significance due to its numerous medical uses. Interpreting various biological flows necessitates a thorough knowledge of the peristaltic mechanism. This paper presents a computational study for the peristaltic motion within vertical asymmetric channels filled with magnetic third grade nanofluid model under the influences of rheological characteristics. Various configurations of the outer boundaries are considered, namely, square wave, multi-sinusoidal wave, trapezoidal wave, and triangular wave. An inclined magnetic field together with nanoparticles and mass concentrations as well as viscous dissipation are considered. Influences of the Dufour and Soret numbers are examined, and the cases of biological scientific assumptions which is known as low Reynolds number and long wavelength are applied. All the computations are obtained numerically using Mathematica symbolical software (ND-Solve). The major outcomes revealed that the square wave shape gives higher pressure gradients near the inlet and outlet parts while the multi-sinusoidal wave gives periodic behaviors of dp/dx. Also, it is better to maximize the variable viscosity coefficient to enhance the rate of heat transfer while, the rate of heat transfer is diminished by the growth in the thermo-diffusion effects as well as variable thermal conductivity coefficient. [ABSTRACT FROM AUTHOR]

Biological evidences are the most commonly encountered physical evidence at the scene of crime. The term "biological evidence" covers a broad range of physical evidence, including hairs, bodily fluids, tissues, and bones, among others. Being a source for both genetic and non-genetic information, they play a vital role in a criminal investigation. Their presence at a crime scene not only aids in the individualization of the donor but also in the reconstruction of the crime scene, thereby leading the investigation in the right direction. With the scientific and technological advancement, the forensic analysis of the biological evidence has witnessed manifold developments. One such approach is flow cytometric technique based on the analysis of a single cell in a complex cellular population. Although this technique is not new to the forensic domain, the improvements in this technique in the past decades have mitigated the limitations which hindered its incorporation in the forensic domain. However, limited literature related to the application of flow cytometric technique for the analysis of the biological evidence, is available. This study provides a review of the application of Flow cytometry in the analysis of biological evidence to pool all the available data so that the lacuna in the literature can be addressed. [ABSTRACT FROM AUTHOR]

Herein, two electrochemical methods based on potentiometric and impedimetric transductions were presented for albumin targeting, employing screen‐printed platforms (SPEs) to make easy and cost‐effective sensors with good detection merits. The SPEs incorporated ion‐to‐electron multi‐walled carbon nanotubes (MWCNTs) transducer. Sensors were constructed using either tridodecyl methyl‐ammonium chloride (TDMACl) (sensor I) or aliquate 336S (sensor II) in plasticized polymeric matrices of carboxylated poly (vinyl chloride) (PVC‐COOH). Analytical performances of the sensors were evaluated using the above‐mentioned electrochemical techniques. For potentiometric assay, constructed sensors responded to albumin with −81.7 ± 1.7 (r2 = 0.9986) and −146.2 ± 2.3 mV/decade (r2 = 0.9991) slopes over the linearity range 1.5 μM–1.5 mM with 0.8 and 1.0 μM detection limits for respective TDMAC‐ and aliquate‐based sensors. Interference study showed apparent selectivity for both sensors. Impedimetric assays were performed at pH = 7.5 in 10 mM PBS buffer solution with a 0.02 M [Fe(CN)6]−3/−4 redox‐active electrolyte. Sensors achieved detection limits of 4.3 × 10−8 and 1.8 × 10−7 M over the linear ranges of 5.2×10−8–1.0×10−4 M and 1.4×10−6–1.4×10−3 M, with 0.09 ± 0.004 and 0.168 ± 0.009 log Ω/decade slopes for sensors based on TDMAC and aliquate, respectively. These sensors are characterized with simple construction, high sensitivity and selectivity, fast response time, single‐use, and cost‐effectiveness. The methods were successfully applied to albumin assessment in different biological fluids. [ABSTRACT FROM AUTHOR]

Purpose: The detection of hydrolysis products of Novichok agents in biological samples from victims is important for confirming exposure to these agents. However, Novichok agents are new class of nerve agent and there have been only few reports on analyses of Novichok agent degradation products. Here, we developed hydrophilic interaction liquid chromatography (HILIC)–tandem mass spectrometry (MS/MS) methods to detect Novichok agent degradation products in human urine with simple pretreatment and high sensitivity. Methods: A Poroshell 120 HILIC-Z column was used to analyze six Novichok agent degradation products. For urine samples, we used a simple pretreatment method, which consisted of deproteinization with acetonitrile and microfiltration. We calculated the pKa values of the OH groups, the log P values, and the molecular weights to investigate the difference in chromatographic behaviors of the Novichok agent degradation products and the degradation products of conventional nerve agents. Results: Six Novichok agent degradation products, including N-(bis-(diethylamino)methylidene)-methylphosphonamidic acid (MPGA), which could not be detected by our previous method, could be analyzed with sufficient peak shape and mutual separation. The detection limits of six Novichok agent degradation products were sufficiently low (1–50 ng/mL) and the calibration curves showed sufficient linearity. The physicochemical parameters of Novichok agent degradation products were different from those of conventional nerve agent degradation products, and this explains the difference in chromatographic behaviors. Conclusion: Six Novichok agent degradation products were successfully analyzed by HILIC–MS/MS. Due to the absence of a derivatization step, throughput performance was higher than our previous derivatization-liquid chromatography–MS/MS method. [ABSTRACT FROM AUTHOR]

The nanocomposite of TiO2 nanoparticles, Au nanoparticles and chitosan was explored for the modification of the pencil graphite electrode surface (TiO2NPs-AuNPs-Chit/PGE). Electrochemical impedance spectroscopy and scanning electron microscopy techniques were used to study the interfacial properties and surface morphology of the modified electrode, respectively. This modified electrode was applied for electrochemical determination of anti-blood pressure drug amlodipine (AML). Electrochemical behavior of AML at the modified electrode was investigated by cyclic voltammetry, chronoamperometry and differential pulse voltammetry techniques. Cyclic voltammetry experiments showed that the oxidation peak current of AML increased and its oxidation overpotential decreased at the modified electrode in comparison to the bare electrode. This observation indicated the electrocatalytic activity of the modified electrode toward AML. Parameters affecting the electrochemical performance of the modified electrode toward AML were optimized. Using differential pulse voltammetry technique under optimized conditions revealed that the oxidation peak currents of AML increased linearly with increasing AML concentration over the range of 0.04–2.8 µM. The detection limit of the method was calculated as 0.015 µM (S/N = 3). Finally, the developed electrode was utilized for the determination of AML in some biological (human serum and urine) and pharmaceutical samples and satisfactory recoveries were obtained. [ABSTRACT FROM AUTHOR]

The phenomenon of biocrystallization has been recorded by researchers for over a century. At the same time, despite the presence of numerous empirical data in this area, there is no unified theoretical basis for the direction under consideration. On this basis, the purpose of the review is to systematize the concepts of biocrystallomics as a new synthetic biomedical science that considers in detail and integratively the processes of bio-associated crystallization occurring both in vitro and in vivo. In this paper historical basis and current status of Russian investigations, which associated with human and animal's biological fluids free and initiated crystallogenesis, are shown. Main stages of building, fundamental rules and problem aspects of biocrystallography as a transformation it to biocrystallomics causes are demonstrated. The definition of this science is presented, its main tasks are characterized. The main directions of biocrystallomics are described, which include experimental biocrystallomics, crystallodiagnostics, crystallopathology, crystallotropic therapy (crystallotherapy), pharmacobiocrystallomics and crystal indication. The existing methods of studying biocrystallogenesis are considered in detail, which are grouped into 3 categories: crystalloscopic, tezigraphic and experimental crystalloscopic. Special attention is paid to the factors that determine the features of the crystallization of biological fluids, among which physical, chemical, biological and mixed are distinguished. The 5 main functions of biocrystallogenesis in biological systems are revealed: protective, nutritivemetabolic, pathogenetic, informational and synthetic-biogenic. The holistic theory of biocrystallomics and its main provisions are presented. So, biocrystallomics as a new integrative science about biocrystals is characterized, and its general ways are given. [ABSTRACT FROM AUTHOR]

Background and purpose: Lysosomal-targeted drug delivery can open a new strategy for drug therapy. However, there is currently no universally accepted simulated or artificial lysosomal fluid utilized in the pharmaceutical industry or recognized by the United States Pharmacopeia (USP). Experimental procedure: We prepared a simulated lysosomal fluid (SLYF) and compared its composition to a commercial artificial counterpart. The developed fluid was used to test the dissolution of a commercial product (Robitussin®) of a lysosomotropic drug (dextromethorphan) and to investigate in-vitro lysosomal trapping of two model drugs (dextromethorphan and (+/-) chloroquine). Findings/Results: The laboratory-prepared fluid or SLYF contained the essential components for the lysosomal function in concentrations reflective of the physiological values, unlike the commercial product. Robitussin® passed the acceptance criteria for the dissolution of dextromethorphan in 0.1 N HCl medium (97.7% in less than 45 min) but not in the SLYF or the phosphate buffer media (72.6% and 32.2% within 45 min, respectively). Racemic chloroquine showed higher lysosomal trapping (51.9%) in the in-vitro model than dextromethorphan (28.3%) in a behavior supporting in-vivo findings and based on the molecular descriptors and the lysosomal sequestration potential of both. Conclusion and implication: A standardized lysosomal fluid was reported and developed for in-vitro investigations of lysosomotropic drugs and formulations.

The cyclic voltammetry method was preliminarily used to study the reversibility nature of the electrochemical behaviour of budesonide (BDN) compound. The square wave-adsorptive stripping voltammetry (SW-AdSV) technique was applied to evaluate an electrochemical reduction of BDN in the phosphate buffer pH 2.5. The ultra-trace graphite working electrode was used to accumulate BDN onto its surface. An SW-AdSV reduction peak was observed in the potential of −0.98 V using Ag/AgCl reference electrode and Pt auxiliary electrode. Different parameters ,such as pH, buffer solutions, accumulations time and potential, frequency, amplitude and scan were investigated, and convection rates parameters were studied to acquire a high reduction response. The repeatability, stability, recovery, calibration curve and limit of detection and quantification parameters were studied to evaluate the analytical performance of the SW-AdSV technique. Repeatability and stability were monitored for 20 µM of BDN to give a 0.29% relative standard deviation (RSD%) that was achieved for five measurements and a very stable current for 120 min. The linearity was evaluated by studying the calibration curve over the range of 2 –25 µM (n = 8), given a linear relation between BDN concentrations and SW-AdSV signals. The limits of detection (LOD) and quantification (LOQ) were calculated to become 40 nM (0.017 ppm) and 0.134 µM (0.0577 ppm), respectively. The developed and validated method was successfully applied to the electrochemical study of BDN in pharmaceuticals and biological fluids.

Abstract Cancer is a major health concern and accounts for one of the main causes of death worldwide. Innovative strategies are needed to aid in the diagnosis and treatment of different types of cancers. Recently, there has been an evolving interest in utilizing nanobodies of camel origin as therapeutic tools against cancer. Nanotechnology uses nanobodies an emerging attractive field that provides promises to researchers in advancing different scientific sectors including medicine and oncology. Nanobodies are characteristically small-sized biologics featured with the ability for deep tissue penetration and dissemination and harbour high stability at high pH and temperatures. The current review highlights the potential use of nanobodies that are naturally secreted in camels’ biological fluids, both milk and urine, in the development of nanotechnology-based therapy for treating different typesQuery of cancers and other diseases. Moreover, the role of nano proteomics in the invention of novel therapeutic agents specifically used for cancer intervention is also illustrated.

Paracetamol is one of the most widely consumed analgesic and antipyretic medications worldwide. It is frequently analyzed in many quality control (QC) laboratories in pharmaceutical companies, either in raw materials or drug products. It was reported that paracetamol self-toxicity often occurs, leading to the frequent analysis of paracetamol in toxicological centers in biological fluids. Green analytical chemistry (GAC) is growing to be a global philosophy; therefore, the high frequency of paracetamol analysis poses potential concerns. Chromatographic analytical methods used for the daily analysis of paracetamol could be a potential risk to the environment or the health of the analysts if not thoroughly considered. The presented study aims to establish greenness assessments of nine HPLC methods used to assay paracetamol in raw materials and drug products and twenty-one HPLC methods. The reason for selecting HPLC methods of analysis to be the core of the study is the known reproducibility, reliability and availability in most QC laboratories. The most commonly used metric systems for greenness evaluation are the Analytical GREEnness (AGREE), the eco-scale assessment (ESA) and the national environmental methods index (NEMI) which have been used in this comparative study. The greenest chromatographic method for the analysis of paracetamol in raw materials and drug products was introduced by Rao et al. (the obtained scores were ESA = 76 and AGREE = 0.62, while the greenest chromatographic method for the analysis of paracetamol in biological fluids was proposed by Modick et al.). The obtained scores were ESA = 85 and AGREE = 0.7. The NEMI tool proved to have limited performance compared to other metric systems, hence it could not be used alone. Accordingly, the collaboration of NEMI results with ESA and AGREE for greenness assessment is highly recommended to reach appropriate conclusions. [ABSTRACT FROM AUTHOR]

Thermal stabilization is important for assuring a sample quality and prevent protein denaturation. Presepsin is a new reliable biomarker of sepsis produced in response to bacterial infections. However, before its inclusion into clinical practice several criteria need to be fulfilled. One of these regards the samples thermostability after a long-term refrigeration in different biological fluids (blood, urine, saliva) that can constitute a confounding factor for Presepsin reliability as diagnostic test. On this light, this review offers an update of studies analyzing presepsin after sample thawing. [ABSTRACT FROM AUTHOR]

The mixture of hyoscine N‐butyl bromide (HBB) and ketoprofen (KTP) is commonly used for the handling of abdominal spasms and pain relief. There are two challenges that restrict the simultaneous assessment of HBB and KTP in biological fluids and pharmaceuticals. The first issue is the difficulty of elution of HBB and the second one is the presence of KTP as a racemic mixture in all pharmaceutical formulations, which obscures its appearance as a single peak. An ultrasensitive and highly efficient liquid chromatography–mass/mass spectrometric (LC–MS/MS) method is designed and validated for the first concurrent assessment of HBB and KTP in spiked human serum and urine, and pharmaceutical formulations. The estimated linearity ranges for HBB and KTP were respectively, 0.5–500 and 0.05–500 ng/ml, with excellent correlation coefficients. Validation results showed that the value of relative standard deviations were <2% for HBB and KTP. The mean extraction recoveries for HBB and KTP were, respectively, 91.04 and 97.83% in Spasmofen® ampoules; 95.89 and 97.00% in spiked serum; and 97.31 and 95.63% in spiked urine. The presented innovative chromatographic approach was utilized for the measurement of trace amounts of coexisting pharmaceuticals in pharmacokinetics studies and routine therapeutic medication monitoring. [ABSTRACT FROM AUTHOR]

The therapeutic efficacy of herbal medicines in the treatment of human diseases or disorders has gained more attention over the years. A survey established that approximately 15 % of patients receiving orthodox medicine also take herbal products, and among these, potential adverse herbto- drug interactions were observed in 40 % of patients. Recently, there have been reports of herbdrug interactions which have impacted on wellness of users resulting in toxicity or loss of therapeutic efficacy of either the herb or the orthodox drug when co-administered. These reports make herb-drug interactions a research area of public interest. This study was embarked upon to evaluate the effect of Ciklavit® used for the management of sickle cell anaemia on the pharmacokinetic profile of proguanil tablets in healthy Nigerian volunteers. Twelve healthy participants were recruited and completed the study after signing a consent form. The study was performed using a single dose, two-way randomized crossover design. The participants were randomly grouped into control and treatment. The treatment group were administered proguanil tablets with Ciklavit® while the control group took proguanil with water only. The blood and urine samples collected at different time interval for 24 hours were analyzed using High Performance Liquid Chromatography. The results obtained, demonstrated that co-administration of Ciklavit® with proguanil altered pharmacokinetic parameters of proguanil but the difference in values were found to be statistically insignificant (p>0.05). The study demonstrated that there are no significant pharmacokinetic interactions between proguanil and Ciklavit® hence the two medicinal agents can be co-administered. [ABSTRACT FROM AUTHOR]

This work proposed the developed of thermo‐sensitive and magnetic molecularly imprinted polymer for the extraction of omeprazole from the human urine and pharmaceutical samples. The ethylene glycol dimethacrylate and N, N′‐methylenediacrylamide were used as the cross‐linkers, poly (N‐vinylcaprolactam) as a thermo‐sensitive monomer, and omeprazole as a template to create molecularly imprinted polymer. The maximum sorption capacity was achieved at a contact time of 15 min, pH=7, temperature of 25 °C, and initial concentration of 20 μg mL−1. Under these conditions, the omeprazole in human urine and pharmaceutical samples were determined by high performance liquid chromatography with ultra‐violet detection. The obtained polymer was characterized by different techniques. The equilibrium data were fitted well with Langmuir isotherm model.The limit of quantification and limit of detection were 0.24 and 0.061 μg mL−1, respectively. Relative standard deviations for inter‐day and intra‐day precisions were 1.78 % and 1.51 %, respectively. Omeprazole extraction recoveries from samples exceeded 93 %. [ABSTRACT FROM AUTHOR]

In this study, a selective and sensitive electrochemical determination of morphine at low concentration was carried out using electropolymerization of 3-methyl-1-phenyl-pyrazole-5-one (MPP) at the surface of a glassy carbon electrode (GCE) which was further modified by electrodeposition of cobalt nanoparticles (Co NPs) onto its surface. The electrochemical studies of morphine were performed using cyclic voltammetric (CV) and differential pulse voltammetric (DPV) techniques. Modification of the electrode surface increased its response to morphine which yielded a relatively wide linear range (2 to 100 μM) and a low limit of detection of 0.12 μM. The analytical characteristics of the sensor towards determination of the morphine were investigated which confirmed a good analytical performance for the sensor. Finally, the sensor was used for monitoring morphine in serum and urine samples as real matrices whose performance was both acceptable and admirable which motivated us to introduce it as a reliable method for determination of morphine in biological fluids.

In forensic sciences, body fluids, or biological traces, are a major source of information, and their identification can play a decisive role in criminal investigations. Currently, the nature of biological fluids is assessed using immunological, physico-chemical, mRNA and epigenetic methods, but these have limits in terms of sensitivity and specificity. The emergence of next-generation sequencing technologies offers new opportunities to identify the nature of body fluids by determining bacterial communities. The aim of this pilot study was to assess whether analysis of the bacterial communities in isolated and mixed biological fluids could reflect the situation observed in real forensics labs. Several samples commonly encountered in forensic sciences were tested from healthy volunteers: saliva, vaginal fluid, blood, semen and skin swabs. These samples were analyzed alone or in combination in a ratio of 1:1. Sequencing was performed on the Ion Gene StudioTM S5 automated sequencer. Fluids tested alone revealed a typical bacterial signature with specific bacterial orders, enabling formal identification of the fluid of interest, despite inter-individual variations. However, in biological fluid mixtures, the predominance of some bacterial microbiomes inhibited interpretation. Oral and vaginal microbiomes were clearly preponderant, and the relative abundance of their bacterial communities and/or the presence of common species between samples made it impossible to detect bacterial orders or genera from other fluids, although they were distinguishable from one another. However, using the beta diversity, salivary fluids were identified and could be distinguished from fluids in combination. While this method of fluid identification is promising, further analyses are required to consolidate the protocol and ensure reliability.

In this paper there are presented some results obtained by open circuit potential and electrochemical impedance spectroscopy measurements from studies performed on the behavior of tribocorrosion on metallic implant biomaterials as: 304L stainless steel, Co/nano-CeO2 nanocomposite layer and Ti6Al4V untreated and oxidized alloy to form a nanoporous TiO2 film. The open circuit potential technique used in measuring the tribocorrosion process provide information on the active or passive behavior of the investigated metallic biomaterial in the biological fluid, before, during friction and after stopping the friction. Thus it clearly show a better behavior of Co/nano-CeO2 nanocomposite coatings as compared with 304L stainless steel to tribocorrosion degradation in Hank solution; as well the better behavior of nanoporous TiO2 film formed annodically on Ti6Al4V alloy surface as compared with untreated alloy to tribocorrosion degradation in artificial saliva Fusayama Meyer. The slight decrease in polarization resistance value resulted from electrochemical impedance spectroscopy measured during friction in the case of the Co/nano-CeO2 nanocomposite layer (four times smaller), compared to 304L stainless steel, whose polarization resistance decreased more than 1000 times during friction shows the higher sensitivity of stainless steel to degradation by tribocorrosion. The same behavior is observed when comparing the polarization resistance of untreated titanium alloy recorded during friction that is about 200 hundred times smaller, while the specific polarization resistance of the oxidized alloy with the nanoporous film of titanium oxide, decreases very little during friction, highlighting the beneficial effect of modifying the titanium alloy by anodic oxidation to increase its resistance to the degradation process by tribocorrosion.

Because of their unique intrinsic physical and chemical properties, carbon nanotubes (CNT) are being used in biological and biomedical applications. The current study proposes a mathematical model to analyze the effect of interfacial nanolayers on heat and mass transfer processes for nanofluid flow. Furthermore, the presence of carbon nanotubes (CNT) in a biological fluid (non-Newtonian fluid) with a reaction effect is investigated using porous surfaces. The uniform transverse magnetic flux was also included in the current study. Using a similarity transformation, the nonlinear partial differential equation is reduced to a set of ordinary differential equations. A phase simulation based on Brownian and thermophoresis factors have been developed for this problem. Optimal nanoparticles in the range of 2–8% have a significant effect on thermal conductivity as well as the thermal performance of the blood flow system. The numerical procedure supported the shooting method, resulting in the desired accuracy. Utilization of the Cason parameter under the effect of nanolayer thermal conductivity has horrendous results. The increase in nanolayer thickness, h = 3–9 nm, enhanced the effective thermal conductivity and thermal performance significantly.

The movement of biological fluids in the human body is a premium field of interest to overcome growing biomedical challenges. Blood behavior shows different behavior in capillaries, veins, and arteries during circulation. In this paper, a new mathematical relation for the nano-layer of biological fluids flows with the effect of TiO2 and Ag hybrid nanoparticles was developed. Further, we explain the engineering phenomena of biological fluids and the role of hybrid nanoparticles in the blood vessel system. The improvement of drug delivery systems by using low seepage Reynolds number was associated with expansion/contraction and was discussed in detail through the rectangular domain. Using similarity transformation, the governing equations were converted into non-linear ordinary differential equations, and the mathematical problem was solved by employing the numerical shooting method. Plots of momentum, temperature, skin friction coefficient, as well as the Nusselt number on different non-dimensionless parameters are displayed via lower/upper porous walls of the channel. It was analyzed that the walls of the channel showed different results on magnetized physical parameters. Values of thermophoresis and the Brownian motion flow of the heat transfer rate gradually increased on the upper wall and decreased on the lower wall of the channel. The important thing is that the hybrid nanoparticles, rather than nano, were more useful for improving thermal conductivity, heat transfer rate, and the nano-layer. [ABSTRACT FROM AUTHOR]

Purpose: The detection of hydrolysis products of nerve agents (alkyl methylphosphonic acids; RMPAs) in biological samples from victims is important to confirm exposure to nerve agents. However, analysis of RMPAs is difficult due to their high hydrophilicity. The aim of this study was to develop ion chromatography–tandem mass spectrometry (IC–MS/MS) methods using commercially available equipment and columns to analyze RMPAs in human urine and serum with high sensitivity and without using complicate techniques. Methods: A Dionex IonPac AS11-HC anion-exchange column was used to analyze six RMPAs (MPA, EMPA, IMPA, iBuMPA, CHMPA, and PMPA). For pretreatments of biological fluids, we developed two pretreatment methods (Method 1: dilution and ultrafiltration; Method 2: removal of chloride ions with Ag cartridges). Results: Six RMPAs including highly hydrophilic methylphosphonic acid and ethyl methylphosphonic acid could be analyzed with sufficient retention times and peak shape. The detection limits of RMPAs were improved using Dionex OnGuard II Ba/Ag/H cartridges and MetaSEP IC–Ag cartridges (urine: 0.5–5 ng/mL; serum: 1–5 ng/mL). These methods were also applied to the test samples for the Organisation for the Prohibition of Chemical Weapons Biomedical Proficiency Tests. Conclusions: RMPAs could be sufficiently analyzed by IC–MS/MS. In addition, the limits of detection were superior to those obtained in our previous study involving LC–MS/MS or derivatization–LC–MS/MS method. For analysis of biological samples, an appropriate pretreatment method can be chosen according to the amount of sample available for analysis and expected RMPA concentrations. [ABSTRACT FROM AUTHOR]

In the present study, on-chip electromembrane surrounded solid phase microextraction (EM-SPME) was employed in the determination of tricyclic antidepressants (TCAs), including amitriptyline, nortriptyline, imipramine, desipramine, maprotiline, and sertraline, from various biological fluids. In this regard, poly(3,4-ethylenedioxythiophene)–graphene oxide (PEDOT-GO) was electrodeposited on an SPME fiber as a conductive coating, then the fiber played the acceptor-electrode role during the extraction. Thus, the immigration of the analytes under the influence of an electric field and their absorption onto the fiber coating were accomplished simultaneously. Under the optimized conditions, the limits of detection for the target analytes were acquired in the range of 0.005–0.025 µg L−1 using gas chromatography–mass spectrometry. The linearity of the method was 0.010–500 µg L−1 for the imipramine and sertraline, 0.025–500 µg L−1 for the amitriptyline, nortriptyline, and desipramine, and 1.000–250 µg L−1 for the maprotiline (R2 ≥ 0.9984). Moreover, this method provided suitable precision and fiber-to-fiber reproducibility, with RSDs ≤ 8.4%. The applicability of the proposed setup was eventually investigated for extraction of the drugs from human bone marrow aspirate, urine, plasma, and well water samples, in which satisfactory relative recoveries, from 93–105%, were obtained. [ABSTRACT FROM AUTHOR]

In the present study, we have designed a highly conductive electrode material niobium carbide (NbC) entangled with copper phosphate (Cu3P2O8). The combined features of the efficient electrocatalyst with improved electrical conductivity, more active sites, with a high surface area were employed for the electrochemical sensing of melatonin (MLT). MLT is a naturally secreted hormone in our brain responsible for maintaining our daily circadian cycle. The detection of such hormones in clinical studies can help maintain several problems. The Cu3P2O8/NbC was initially characterized to analyze the physicochemical properties. The high crystalline Cu3P2O8 resembled a self-assembled flake ball-like structure entangled with NbC sheets. The synergistic effect between the catalyst enhances the electrochemical performance of MLT. The Cu3P2O8/NbC fabricated glassy carbon electrode obtained an enhanced oxidation response of MLT. The linearity range of MLT was about 0.014–1517.68 μM with a low limit of detection of about 0.0083 μM. The fabricated electrode showed high selectivity to the interfering compounds added and the sensitivity was about 5.137 μA μM–1 cm–2. The real samples showed good results at the Cu3P2O8/NbC/GCE. The Cu3P2O8/NbC/GCE will be more efficient and reliable in detecting the employed drugs or any other analytes of choice. Thus, the low cost, with improved electrochemical performances and significant features of the prepared electrode will be of great interest. [ABSTRACT FROM AUTHOR]

Dissolved oxygen (DO) is deeply involved in preserving the life of cellular tissues and human beings due to its key role in cellular metabolism: its alterations may reflect important pathophysiological conditions. DO levels are measured to identify pathological conditions, explain pathophysiological mechanisms, and monitor the efficacy of therapeutic approaches. This is particularly relevant when the measurements are performed in vivo but also in contexts where a variety of biological and synthetic media are used, such as ex vivo organ perfusion. A reliable measurement of medium oxygenation ensures a high-quality process. It is crucial to provide a high-accuracy, real-time method for DO quantification, which could be robust towards different medium compositions and temperatures. In fact, biological fluids and synthetic clinical fluids represent a challenging environment where DO interacts with various compounds and can change continuously and dynamically, and further precaution is needed to obtain reliable results. This study aims to present and discuss the main oxygen detection and quantification methods, focusing on the technical needs for their translation to clinical practice. Firstly, we resumed all the main methodologies and advancements concerning dissolved oxygen determination. After identifying the main groups of all the available techniques for DO sensing based on their mechanisms and applicability, we focused on transferring the most promising approaches to a clinical in vivo/ex vivo setting. [ABSTRACT FROM AUTHOR]

Superhydrophobic biological fluid‐repellent surfaces (SBFRSs) have attracted great attention in the treatment of blood and urine‐related diseases because of their unique wettability and compatibility, which creates a new path for the development of medical apparatus and instruments, and are expected to create advances in various fields. Here, this review provides an up‐to‐date summary of research progress on the repellent mechanism and application of SBFRSs. The underlying physical and chemical principles for designing superhydrophobic surfaces are first introduced. Then, the dialectical influences of solid‐liquid interactions between superhydrophobic surfaces and biological fluids on the wettability and compatibility are emphatically expounded. Subsequently, attention is drawn to the recent applications of SBFRSs in biomedical fields, such as surgical medical apparatus, implant materials, extracorporeal circulation devices, and biological fluid detection. Finally, the outlook and challenges in terms of employing SBFRSs are also discussed. This review is expected to provide a comprehensive guidance for the preparation of SBFRSs with compatibility and long‐term superhydrophobic stability that is closely related to clinical applications. [ABSTRACT FROM AUTHOR]