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This study assessed the concentrations of several trace and heavy metals in bottled drinking water. A total of 27 samples were collected from Yemeni markets. The ICP-MS (inductively coupled plasma-mass spectrometry) technique was utilized to analyze the levels of Li, Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Se, Rb, Ag, Cd, Cs, Ba, Hg, Tl, Pb, and U. Furthermore, the study also examined the levels of total dissolved solids (TDS), electrical conductivity (EC), and pH in the collected samples. The concentrations of the elements in the bottled drinking water samples were compared to the maximum allowable concentration (MAC) values for these elements in drinking water, set by the World Health Organization (WHO) and Yemen’s Ministry of Water and Environment (YMWE). The limit of detection (LOD) and recovery ranged from 0.0003 to 1.86 μg/l, 80 to 120 %, respectively. Only trace elements Mn and Pb were detected in all samples at concentrations below the LOD. Out of the elements examined, only Hg exceeded the acceptable limits defined by both the WHO and YMWE in most of the samples.

Introduction: Mycotoxins are toxic metabolites produced by fungi that commonly contaminate foods. As recommended by the World Health Organization, total diet study (TDS) is the most efficient and effective way to estimate the dietary intakes of certain chemical substances for general populations. It requires sensitive and reliable analytical methods applicable to a wide range of complex food matrices and ready-to-eat dishes. Objectives: A novel strategy with high selectivity and sensitivity, incorporating three methods based on ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS), was designed for measuring 43 mycotoxins in dietary samples in a China TDS. Methods: The 43 mycotoxins were divided into 3 groups for analysis to achieve better performance. For each group, an UHPLC-MS/MS method was developed to determine the target compounds after clean-up by solid phase extraction. A total of 21 isotope internal standards were employed for accurate quantitation. Method validation in terms of linearity, selectivity, sensitivity, accuracy, and precision was performed for all the 43 mycotoxins in 12 complex food matrices. Results: The limits of detection (LODs) and limits of quantitation (LOQs) were 0.002–1 ng mL−1 and 0.006–3 ng mL−1, respectively. The method recoveries of the 43 mycotoxins spiked in 12 food categories were in the range of 60.3%–175.9% after internal standard correction, with relative standard deviations (RSDs) below 13.9%. For practical application, this method was utilized for 72 dietary samples collected from 6 provinces in the 6th China TDS. More than 80% of the samples were found contaminated by mycotoxins. DON, SMC, FB1, ZEN, BEA, ENNB1, and ENNB were most detected. Conclusions: The proposed methods with high sensitivity, accuracy, and robustness provide powerful tools for multi-mycotoxin monitoring and dietary exposure assessment, allowing 43 mycotoxins, including some emerging mycotoxins, to be accurately investigated in a total diet study for the first time.

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 this work, we did our best to develop a novel and interesting analytical method based on coupling of spectrofluorimetry with first-order multivariate calibration techniques for simultaneous determination of lead (Pd), zinc (Zn) and cadmium (Cd) in HeLa cells. To achieve this goal, quenching of the emission of graphene (GR) was individually investigated in the presence of Pb, Zn and Cd and then, according to the linear ranges obtained from individual calibration graphs, a multivariate calibration model was developed based on modeling of the quenching of the emission of GR in the presence of the mixtures of Pb, Zn and Cd. First-order multivariate calibration models were constructed by partial least squares (PLS), principal component regression (PCR), orthogonal signal correction-PLS (OSC-PLS), continuum power regression (CPR), robust continuum regression (RCR) and partial robust M-regression (PRM) and their performances were evaluated and statistically compared. Finally, the OSC-PLS was chosen as the best model with the best practical performance for analytical purposes.

A simple, accurate, precise, sensitive and selective spectrofluorimetric method was developed and validated for the determination of Atorvastatin calcium (ATV), an HMG-CoA reductase inhibitor, in its pure and tablet dosage form. The proposed method was based on direct measurement of the native fluorescence of ATV. Fluorescence analysis was accomplished by using an emission wavelength 385 nm after excitation at the wavelength of 270 nm in acetonitrile, without difficult preparation steps of the sample solution such as separation, extraction, pH adjustment or derivatization. All variables affecting the fluorescence intensity such as measurement time, temperature, and diluting solvent were investigated and optimized. Under the typical conditions, a validation study for linearity, range, accuracy, precision, selectivity and robustness of the proposed method was implemented according to ICH guidelines. The fluorescence intensity was linear over concentration range of (0.4–12) μg/ml (r = 0.9999), and the lower limits of detection and quantification were 0.079 and 0.24 μg/ml, respectively. Good accuracy and precision results were obtained through using the presented method with excellent mean recovery value 100.08 ± 0.32 which was in the acceptable range (98.0–102.0%), and RSD

In recent years, food quality and safety have gained increasing attention. However, due to the complexity of food composition, accurate classical extraction techniques require using toxic organic solvents. The development of green extraction techniques has come to the fore to repress this drawback. In this review, the recent novel methodologies for extracting pollutants from food samples that fulfill the principles of green chemistry were summarized. The use of sorbent-based techniques, such as solid-phase microextraction (SPME), and stir-bar sorbent extraction (SBSE), and advanced techniques such as ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), enzyme-assisted extraction (EAE), pressurized liquid extraction (PLE) and supercritical fluid extraction (SFE), for improving and accelerating extraction efficiency and reducing solvent consumption are highlighted. Lastly, future perspectives on the implementation of these eco-friendly methodologies are described along with the technological advancements required.

People frequently administer Tizanidine (TIZ) to treat spasticity resulting from diseases like multiple sclerosis or spinal cord injuries. It also helps prevent muscle spasms. It helps to relax and release tense and stiff muscles by inhibiting specific nerve signals in the brain and spinal cord. The technique employed in this study made use of the unique ability of benzofurazan to confer fluorescent character when reacted with TIZ at specific conditions. This fluorogenic property was harnessed to evolve a remarkably sensitive, affordable, and selective method to quantify TIZ. The resulting yellow fluorescent product was observedat a wavelength beam of 532.9 nm, and an excitation wavelength beam of 474.9 nm was applied. By looking at the response across the TIZ concentration, the calibration chart's linearity was assessed in the range of 40-500 ng/mL. By computation, the approach's detection level (LOD) was determined to be 11.9 ng/mL, while the quantitation level was approximated to be 36 ng/mL. All pertinent factors impacting the strategy's efficacy were thoroughly inspected and adjusted accordingly. The proposed strategy was validated following the guidelines outlined by the ICH. The outcomes confirmed the method's capability for the accurate quantifying of TIZ in tablets, spiked plasma, and pharmaceutical assessing content uniformity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Detecting the furfural concentration in Baijiu can be used to assess the quality of Baijiu, allowing for the optimization of processing techniques and the enhancement of overall quality. In this paper, a fluorescence-enhanced method based on carbon dots (o-CDs) is developed for the furfural determination in Chinese Baijiu. In an environment full-filled with ·SO 4 - and ·OH, furfural undergone a direct surface reaction with the ortho-diamino groups at o-CDs. The created furan-based imidazole increased the surface electron density, leading an emission enhancement and color changes from orange to green. Thereby, a linear fluorescence response of o-CDs-TA to furfural is established in water with a detection limit of 30.5 nM. Finally, after ethanol correction it is used to determine furfural in Chinese Baijiu with high precision and reproducibility, providing a new strategy with low-cost and high sensitivity. In particular, the idea of covalently connecting target molecule to the CDs surface via the assistance of free radical opens a new avenue to merge the nanoscale and molecular realms through implementing chemical role into carbon nanostructures., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The high speed enrichment of benzoylurea insecticides (BUs) in complex matrices is an essential and challenging step. The present study focuses on the synthesis of a hierarchical pore nitrogen-doped carbon material for magnetic solid phase extraction (MSPE) of BUs. This material was prepared through the carbonization of a composite material ZIF-67@MCA which assembly with hydrogen-bonded organic frameworks (melamine-cyanurate, MCA) and zeolitic imidazolate framework (ZIF-67) at room temperature. The optimal adsorption effect is achieved when the mass ratio of ZIF-67 to MCA is 1/3, and the carbonization was performed at 600 °C, the such obtained carbon material was denoted as 1/3ZIF-67@MCA-DCs-600. The material was characterized with various physical methods including X-ray diffractometry (XRD), Fourier transform infrared spectrometry (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), Brunauer-Emmett-Teller (BET), vibrating sample magnetometer (VSM), water contact angle measurement, Raman spectrometry. 1/3ZIF-67@MCA-DCs-600 exhibits a macro-mesoporous 3D structure with a high degree of nitrogen doping and relatively large specific surface area, making it suitable for magnetic solid phase extraction (MSPE). The adsorption of BUs with concentration of 100 ng mL -1 can reach equilibrium within 5 s. The interaction between BUs and the adsorbent, facilitated by π-π stacking, hydrophobic interactions, hydrogen bonding forces, as well as the material's porosity, enables efficient extraction recoveries ranging from 45 % to 92 %. The enrichment of BUs was achieved through the establishment of an MSPE method under optimized conditions, which was further coupled with high performance liquid chromatography (HPLC) for the determination of the four BUs. The linear range spans from 5 ng ml -1 to 1000 ng ml -1 with the correlation coefficient (R 2 ) of ≥ 0.99, Meanwhile, the detection limit for these four BUs falls within the range of 0.01 to 0.10 ng ml -1 . The material exhibits good reusability and can be reused for at least 5 cycles. Inter day and intra-day precision ranges from 2.1-7.9 % and 1.0-5.4 %, respectively. The method demonstrates a high level of reliability in practical applications for the determination of BUs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

In this study, an analytical method based on the modified QuEChERS and gas chromatography tandem mass spectrometry was proposed to determine 15 phthalic acid esters in edible oils including dimethyl phthalate, diethyl phthalate, diisobutyl phthalate, dibutyl phthalate, bis(4-methyl-2-pentyl) phthalate, bis(2-ethoxyethyl) phthalate, dipentyl phthalate, dihexyl phthalate, benzyl butyl phthalate, bis(2-n-butoxyethyl) phthalate, dicyclohexyl phthalate, di-n-heptyl phthalate, diphenyl phthalate, di-n-octyl phthalate, and dinonyl phthalate. Calibration curves with good correlation coefficients (R > 0.990) were obtained in the range of 4–2000 μg kg−1. The LODs and LOQs were from 0.02 to 8.00 μg kg−1 and from 0.07 to 26.68 μg kg−1, respectively, which were significantly lower than the previous studies. Moreover, good recoveries varied from 70.11 % to 115.33 %, while repeatability ranged from 3.97 % to 11.55 %. The results showed that DBP, DIBP, and DEHP were detected in edible oils. The foregoing findings suggested that the proposed approach might be used to detect phthalic acid esters in edible oils.

In the last decades, the use of electrochemical and electrode modification-based biosensors has aroused great research interest in widely different applications such as medical diagnostics, drug analysis, environmental monitoring, food analysis, and biochemical analysis. Moreover, the use of various nanomaterials for electrode modifications and the production of these modifications based on the layer-by-layer film deposition techniques have provided significant advantages in the production of stable and sensitive sensors that provide a large surface area. In this review, the applications of electrochemical methods developed for the determination of major biomarkers that are important in the diagnosis of different diseases are discussed. In three main categories, diseases and related biomarkers, electrochemical sensors and modification strategies, and applications of prepared electrodes according to the layer-by-layer strategy are described. Current biosensors, operating conditions, some validation characteristics, and applications reported to detect several biomarkers in the last four years are presented to the researchers in a table. Moreover, conclusions and future perspectives are presented, highlighting some ongoing challenges and some topics for improvement to maximize sensor sensitivity.

Oncoviruses are responsible for less than half of cancers in humans. In virus-related human oncogenesis, a multi-step process leads normal cells to transform into cancerous cells in the body. Among the various oncoviruses are human papillomavirus (HPV), Epstein-Barr virus (EBV), hepatitis B virus (HBV) and hepatitis C virus (HCV), human immunodeficiency virus (HIV), human herpesvirus (HHV-8), human lymphotropic virus-1 (HTLV-1), Merkel cell polyomavirus (MCV). The Pap smear test is critical in HPV screening, but its sensitivity is relatively low in cervical lesions, and the probability of giving false results is high. In this situation, create an alternative screening method. Therefore, the applied electroanalytical measurement techniques and electrode systems are important for detecting oncoviruses using electrochemical biosensors. Electrochemical sensor strategies such as genosensors, CRISPR-based recognition assay, aptamer-based biosensors, and immunosensors are used for the detection of oncoviruses. Major viruses causing cancer and oncovirus-related cancer types and electrochemical sensor strategies are described in the review. Studies that have been published in recent years are reported in tables for explaining details. This review considered the articles published in the last 10 years. The biosensor studies for cancer-causing viruses get gradually increased.

ABSTRACT: Four toxic residues in gelatin capsule shells after ethylene oxide (EO) sterilization were identified by gas chromatography-mass spectrometer (GC-MS) and they were ethylene oxide, 2-chloroethanol, acetaldehyde, and 1,4-dioxane. The generation pathway and mechanism of the 2-chloroethanol, acetaldehyde, and 1,4-dioxane were further investigated. Additionally, a simple and rapid gas chromatography-flame ionization detector (GC-FID) method was established and fully validation including specificity, linearity, sensitivity, and accuracy were conducted according to ICH Q2 (R1) guidelines. The results showed good linearities with coefficients (r) higher than 0.9999 for four analytes. The limits of detection (LODs) of four analytes were in the range of 0.025-1.0 μg·mL−1 and the limits of quantitation (LOQs) were in the range of 0.05-2.0 μg·mL−1. The recoveries of four impurities were ranged from 83.0 % to 114.9 %. The repeatability and inter-day precisions were in the ranges of 0.7-3.3%. This validated GC-FID method provided an approach for capsule manufacturers to routinely monitor residues in gelatin capsule shells, design and optimize the storage time after sterilization and judge whether it can be released from the factory after sterilization. It can also be used for enterprises and regulatory bodies to routinely control the quality of hard gelatin capsule shells.

A simple semi-automated dispersive liquid–liquid microextraction system was designed and used for off-line preconcentration and determination of nickel (II) ion in some food samples. The methodology submitted in the present work is based upon the microextraction of [Ni(C38H28O2N)2] complex employing an orange peel oil (OPO) as an extractant without a dispersing solvent and the estimation of nickel (II) ion in sediment by electrothermal atomic absorption spectrometry (ETAAS). 3 mL of sample solution, 0.5 mL of acetate buffer (pH 6), and 300 µL of the complexing agent (1-[4-[(2-hydroxynaphthalen-1-yl)methylideneamino] phenyl]ethanone) (HNE) dissolved in OPO were automatically transferred to separation tube and the cloudy solution was obtained by dispersing OPO as droplets throughout the aqueous phase using nitrogen gas. Under the optimized conditions, the analytical methodology used in this study provided a good efficiency in term of sensitivity and selectivity where the calibration plot was linear in the range of 5–150 ngL–1, while, the enhancement factor (EF) and the detection limit were 300 and 0.87 ngL–1, respectively for a sample volume of 3 mL. On the other hand, the method was completely free of most potential interferences. Certified reference wheat sample (NCS ZC11018) and some food samples were used to evaluate the developed method and results were compared using ICP–MS. Moreover, the new [Ni(C38H28O2N)2] complex was synthesized and characterized using diverse characterization techniques.

Double deposition and double stripping steps mode was used for the first time in combination with a flow system for anodic stripping voltammetric determination of As(III) ions. The proposed way of the voltammetric measurements leads to a decrease of the detection limit as compared to the values obtained using a traditional three-electrode system thanks to an initial preconcentration of the analyte on the first working electrode as well as the significant increase of the selectivity of As(III) determination thanks to the application of a flow system. Optimization of the analytical procedure was performed. The calibration curve of As(III) determination was a straight line in the range from 1 × 10 -9 to 5 × 10 -8  mol L -1 . The estimated detection limit was 4.8 × 10 -10  mol L -1 (deposition time of 120 s at both working electrodes). The repeatability of the proposed procedure calculated as RSD% for As(III) at a concentration of 1 × 10 -8  mol L -1 was 3.8 % (n = 7). The tolerable limit of Cu(II) excess was significantly increased thanks to the solution exchange after the first deposition step. The correctness of the proposed procedure was confirmed by analysis of a real water sample and lake water certified reference material by obtaining satisfactory recovery values., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Iwona Geca reports financial support was provided by National Science Centre Poland. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Sensitively analyzing phenolic endocrine-disrupting chemicals (EDCs) in environmental substrates and aquatic organisms provides a significant challenge. Here, we developed a novel porous hyper-crosslinked ionic polymer bearing cyano groups (CN-HIP) as adsorbent for the highly efficient solid phase extraction (SPE) of phenolic EDCs in water and fish. The CN-HIP gave an excellent adsorption capability for targeted EDCs over a wide pH range, and the adsorption capacity was superior to that of several common commercial SPE adsorbents. The coexistence of electrostatic forces, hydrogen bond, and π-π interactions was confirmed as the main adsorption mechanism. A sensitive quantitative method was established by coupling CN-HIP based SPE method with high-performance liquid chromatography for the simultaneously determining trace bisphenol A, bisphenol F, bisphenol B and 4-tert-butylphenol in fresh water and fish. The method afforded lower detection limits (S/N = 3) (at 0.03-0.10 ng mL -1 for water and 0.8-4.0 ng g -1 for fish), high accuracy (the recovery of spiked sample at 88.0%-112 %) and high precision (the relative standard deviation < 8.5 %). This work provides a feasible method for detecting phenolic EDCs, and also opens a new perspective in developing functionalized cationic adsorbent., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Clozapine (CLO) is an atypical antipsychotic drug indicated for the treatment of schizophrenia. The treatment effectiveness of CLO is better than that of other atypical antipsychotics, and it has the advantage of being able to determine its effectiveness by measuring its concentration in the patient's blood. Thus, sensitive, selective, and accurate determination of CLO in blood is highly significant for treatment monitoring. This study describes the design and fabrication of a molecularly imprinted polymer (MIP)-based electrochemical sensor for CLO determination. This is the first MIP-based electrochemical application in the literature for CLO determination. Employing the thermal polymerization approach, the MIP was formed on the glassy carbon electrode (GCE) using CLO as the template, trans-3-(3-Pyridyl)acrylic acid (3,3-TA) as the functional monomer, and the support of zinc oxide nanoparticles (ZnO NPs). Elaborate characterizations in terms of surface morphology and electrochemistry were performed via scanning electron microscopy (SEM), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) methods. An indirect approach was employed to determine CLO in standard solution, real human biological samples, and tablet formulation, using 5 × 10 -3  M [Fe(CN) 6 ] 3-/4- solution as the redox probe. The limit of detection (LOD) values for the standard solution and serum sample were calculated as 2.9 × 10 -11  M and 6.01 × 10 -12  M, respectively. These values and recovery studies confirmed the sensor's sensitivity and feasibility. The measurements in the presence of similarly structured compounds (olanzapine and quetiapine fumarate) verified the sensor's superior selectivity. Moreover, the developed sensor's performance was compared and verified using an LC-MS/MS method using the student's t-test and F-test., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Determination of olefins in pyrolysis oils from waste plastics and tires is crucial for optimizing the pyrolysis process and especially for the further advanced valorization of these oils in terms of the circular economy. Identifying olefins, even using high-resolution techniques like GC×GC, is challenging without TOF-MS, which allows modification of the ionization step. Currently, the only method for determining olefins in plastic pyrolysis oils is GC-VUV, recently standardized as ASTM D8519. However, TOF-MS and VUV are not affordable instruments for many research teams working on plastics recycling. This paper introduces a simple method for the selective micro-scale adsorption of olefins over AgNO 3 /SiO 2 , followed by the GC×GC-FID analysis. Olefins are determined indirectly from the loss of chromatographic area in respective hydrocarbon groups before and after removal. Only 50 μL sample and 15 min of sample separation are needed. Our method was extensively validated and provides a reliable determination of olefin content in a wide range of pyrolysis oils from plastics and tires and their products after mild hydrotreatment. It is affordable to all researchers and industrial companies working on plastics recycling by thermochemical processes as it does not require an MS detector., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Milos Auersvald reports financial support was provided by Ministry of Education Youth and Sports of the Czech Republic. Petr Straka reports equipment, drugs, or supplies was provided by Technology Agency of the Czech Republic. Petr Vozka reports financial support was provided by National Science Foundation. Petr Vozka reports financial support was provided by Cal State LA RSCA. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

In this study, silica@chitosan-glutaraldehyde (Si@Cs-G) was synthesized as a novel adsorbent for extraction of Penicillin G (PG) from the synthetic and real samples followed by HPLC determination. The synthesized adsorbents were characterized by the scanning electron microscopy (SEM), X-ray diffraction (XRD), fourier transform infrared (FTIR), dynamic light scattering (DLS), transmission electron microscopy (TEM) and nitrogen adsorption–desorption techniques. The factors influencing the extraction efficiency including pH, sorbent dose, extraction time, extraction solvent type and its volume were investigated and optimized.Under the optimal conditions (sorbent dosage: 25 mg, desorption solvent (acetonitrile) with volume of 0.75 mL; pH: 6 and extraction time: 50 min), the Si@Cs-G demonstrated high efficiency and linearity (R2 > 0.999) with the concentration of penicillin G ranging from 1 to 300 μg L−1. Extraction recovery in synthetic samples was 98.977%, with LOD = 0.493 μg L−1, LOQ = 1.638 μg L−1 and RSD

An UPLC- mass spectrometry method has been proposed for the screening of carbaryl residues in fresh vegetables. Carbaryl treated samples of lettuce, cucumber and spinach were procured and analyzed for a time period of fifteen days to find out the amount of carbaryl residue. A simple and effective liquid–liquid sample extraction technique has been implemented for extraction of carbaryl. Multiple reactions monitoring analysis mode considering two daughter transitions was used for quantitation and confirmation analysis of carbaryl. The developed method has been authenticated by establishing various validation parameters including, linear ranges (0.001–5.0 µg/mL), percent recovery, reproducibility (precision), limits of detection (0.0003 µg/mL) and limits of quantification (0.0009 µg/mL). The recoveries were obtained in the range of 96.0 and 99.5% (RSD

The delegated work entails the simultaneous quantification and validation of a panel of common antipsychotic compounds in dosage form using the UPLC method. The antipsychotic medications used in the study were; Amisulpride, Risperidone, Paliperidone, Ziprasidone, Aripiprazole and Lurasidone. Acquity UPLC@BEH shield RP C18 (100 mm X 2.1 mm id, 1.7 m particle size) column was used to separate the samples with gradient elution consisting of 0.1% TFA and ACN with a PDA detector. The entire analysis took only 7 min with a 0.3 ml/min flow rate, 1 µl injection volume and a 45 °C column oven temperature. The current approach provides good resolution and low solvent consumption in a short amount of time. In most Quality Control laboratories, time-consuming methods and distinct mobile phases are used for different dosage forms of pharmaceuticals, however, the proposed method saves time and money by removing the need to change mobile phases. As a result, the method can be used in QC laboratories where time-consuming methods are used with different mobile-stationary phases. Antipsychotic drug analysis is mainly utilised in QC laboratory and forensic toxicology to monitor medication therapy or to explain the cause of intoxication in human performance and post-mortem situations.

High interference and narrow application range are key of bottleneck of recent fluorescence analysis methods, which limit their wide application in the sensing field. Therefore, to overcome these disadvantages, a ratiometric fluorescence sensing system utilizing berberine (BER) and silver nanoclusters protected by dihydrolipoic acid (DHLA-AgNCs) was constructed for the first time in this work, to achieve determination of BER and daunorubicin (Dau). BER aqueous solution (non-planar conformation) has no fluorescence emission. When it was mixed with DHLA-AgNCs, the conformation of BER became planar, producing fluorescence emission at 515 nm besides the fluorescence emission peak of DHLA-AgNCs at 653 nm. With the increase of BER concentration added in system, the fluorescence intensity of BER (planar conformation) at 515 nm increased obviously and the fluorescence intensity of DHLA-AgNCs decreased slightly. Therefore, the dual emission fluorescence sensing system was constructed based on a fluorescence substance and non fluorescence substance, to achieve determination of BER. Meanwhile, based on the bridging effect of BER and fluorescence resonance energy transfer effect from Dau, the altering of two peaks intensity was utilized to achieve determination of Dau. Thus, this dual emission sensing system can not only be used for fluorescence analysis of BER and its analogues, but also based on the bridging effect of BER, allowing the determination of Dau and its analogues that could not be directly measured with silver nanoclusters, expanding the application range of traditional dual emission detection systems. Meanwhile, this system has strong anti-interference ability and low toxicity to the human body and less pollution to the sample and environment. This provides a new direction and universal research strategy for the construction of new fluorescence sensing systems in the future for the analysis of target substances that cannot be directly detected with conventional fluorescence analysis methods., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Fluorescence analysis has attracted much attention due to its rapidity and sensitivity. The present work describes a novel fluorescence detection method for acid phosphatase (ACP) on the basis of inner-filter effect (IFE), where MnO 2 nanosheets (MnO 2 NSs) and vitamin B 2 (VB 2 ) are served as absorbers and fluorophores, respectively. In the absence of ACP, the absorption band of MnO 2 NSs overlaps well with the excitation band of VB 2 , resulting in effective IFE and inhibition of VB 2 fluorescence. In the presence of ACP, 2-phospho-L-ascorbic acid trisodium salt (AAP) is hydrolyzed to generate ascorbic acid (AA), which efficiently trigger the reduction of MnO 2 NSs into Mn 2+ ions, causing the weakening of the MnO 2 NSs absorption band and the recovery of VB 2 fluorescence. Further investigation indicates that the fluorescence recovery degree of VB 2 increases with the increase of ACP concentration. Under selected experimental conditions, the proposed method can achieve sensitive detection of ACP in the ranges of 0.5-4.0 mU/mL and 4.0-15 mU/mL along with a limit of detection (LOD) as low as 0.14 mU/mL. Finally, this method was successfully applied for the detection of ACP in human serum samples with satisfactory recoveries in the range of 95.0 %-108 %., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The current work proposed a new green procedure that is not sophisticated to recognize and determine the Al(III) ions in multiple water samples. The suggested method was conducted based upon the direct immobilization of aurintricarboxylic acid reagent into the mesoporous silica nanospheres to shape a unique and novel solid sensor. Al(III)-ATA red-complex has been formed at pH 4.0 and spectrophotometrically measured at 525 nm. Moreover, the complexation was reversible, and the ATA sensor retained his functionality even after six-time reuse/cycles using EDTA as eluent. Univariate and multivariate (partial least squares 1, PLS-1) calibration techniques were utilized for calculating the figures of merit for the determination of the Al(III) ions. The obtained calibration curve was linear from 2.0 to 70 ppb Al(III) ions concentration. The developed method has a detection limit of 3.5 ppb. In addition, the ATA sensor showed high adsorption capacity value (118.53 mg/g) which gives it a great advantage to be applicable as nanocollector for trapping Al(III) ions. The novel ATA sensor showed high degree of selectivity, sensitivity, reproducibility, and stability. The current study explores the effectiveness of the ATA sensor for the first time to produce a green solid sensor to determine the trace amount of Al(III) in diverse water types; tap, mineral, river, well, and sea water.

A typical drug used to treat Parkinson's disease is called rasagiline. It belongs to an assortment of drugs known as monoamine oxidase inhibitors, which function by raising dopamine levels in the brain. This work created a unique spectrofluorimetric method for the analytical assay of rasagiline for the first time. The approach utilized the synergistic utility of the fluorogenic properties of benzofurazan and salting-out assisted liquid-liquid extraction. By combining these techniques an ultrasensitive, and highly selective methodology for the assay of rasagiline was established. Measurements were made of the resultant yellow fluorescent product at 533 nm by applying an excitation wavelength of 475.3 nm. The calibration graph was examined to assess its linearity across a range of 30-600 ng/ml. Through estimation, the limit of detection was discovered to be 8.9 ng/ml, while the quantitation limit was estimated to be 27 ng/ml. All relevant parameters influencing the fulfillment of the developed method were thoroughly examined and tuned. Following the directives set by the (ICH) the suggested approach was confirmed and demonstrated its capability for the accurate determination of rasagiline in tablets, as well as for testing content uniformity. The incorporation of salting-out assisted liquid-liquid extraction technology enables effective tracking of rasagiline in plasma samples, providing a novel and innovative approach for its analysis in biological matrices., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

An effective herbal medicinal prescription of Shengjiang Xiexin decoction (SXD) was used in treating the inflammatory bowel disease in clinic. In this study, an ultrafast liquid chromatographytandem mass spectrometry (UFLCMS/MS) method was developed to separate and to simultaneously determine 14 major active ingredients in SXD. Chromatographic separation was successfully accomplished on an Acquity BEH C18 (100 mm×2.1 mm, 1.7 μm) column using gradient elution with 0.1% (v/v) formic acid water (A) and 0.1% (v/v) formic acid in methanol (B). Negative and positive electrospray ionization tandem mass spectrometry was used to detect the 14 analytes using its selective reaction monitoring (SRM) mode. A good linear regression relationship for each analyte was obtained over the range from 3.88 ng/mL to 4080 ng/mL. The precision was evaluated by intra- and inter-day assays with a relative standard deviation (RSD) of less than 6.25%. The recovery measured at three concentration levels varied from 98.72% to 103.47%. The overall limits of quantification (LOQ) ranged from 2.05 ng/mL to 4.72 ng/mL. The method was successfully implemented in the qualitative and quantitative analyses of the 14 chemical constituents in SXD. The results showed that the developed UFLCMS/MS method was linear and accurate. The method could be used reliably as a quality control method for SXD.

Histamine is crucial for controlling a variety of physiological processes and its dysregulation is linked to various pathological conditions, including allergic disorders, autoimmune diseases and inflammatory conditions. Herein, a novel fluorescence chemo sensor was produced to measure histamine in the pure form and spiked human plasma matrix. The proposed method is based on chemical transformation of histamine into a fluorescent product, N-(2-(1H-imidazol-4-yl) ethyl)-2-bromoacetamide, exhibiting unique fluorescence properties compared to non-fluorescent histamine molecule. This transformation occurs through a sequence of chemical reactions involving the interaction of histamine with trimethylamine, resulting in the formation of a nucleophilic intermediate that subsequently reacts with electrophilic bromoacetyl bromide. The transformed fluorescent product demonstrates an emission at 340 nm after being excited at 250 nm. Significant concentration-dependent fluorescence enhancement was obtained enabling histamine determination. The procedures were examined for accuracy, precision, selectivity, and robustness in line with the ICH M10 recommendations. The method exhibits a lower limit of quantification at 0.25 ng/mL and dynamic detection throughout a linearity range of 1-200 ng/mL, providing accurate assessment of histamine in the plasma matrix., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Determination of lithium ions is very important for extraction of lithium from salt lakes. Electrochemical sensor is an ideal choice, but it is not available so far. Here, a voltammetric sensor based on lithium iron phosphate (LiFePO 4 ) was developed. Single-crystal LiFePO 4 dominated by the (010) lattice plane was synthesized using hydrothermal method; it had good selectivity for lithium ions. Lithium ions were preferentially intercalated into LiFePO 4 even if molar ratio of sodium ions, potassium ions, magnesium ions or calcium ions to lithium ions reached 10:1. The intercalation and deintercalation of interfering ions should be avoided because this reduced the selectivity of LiFePO 4 for lithium ions. Lithium ion concentration of synthetic Uyuni Salt Lake solution was determined using the standard addition method. The measurement result was only 0.34 % higher than the theoretical value. The sensor provides a highly selective lithium ion analysis method at an extremely low cost, which was very promising to be widely used., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

In this study, a new fluorine-functionalized covalent organic framework (F-COF) was designed and fabricated by the direct polycondensation of tris(4-aminophenyl)amine and 2,3,5,6-tetra-fluoroterephthaldehyde for the first time. F-COF exhibited a remarkably enhanced adsorption capability compared with that of the fluorine-free COF. The favorable adsorption of aflatoxins was attributed to multiple interactions including pseudo hydrogen bond, F-O, π-π, F-π interactions and hydrophobic interactions between F-COF and aflatoxins. By coupling F-COF based solid phase extraction with high-performance liquid chromatography equipped with fluorescence detector, a rapid and sensitive method for determining aflatoxins (aflatoxin B 1 , B 2 , G 1 and G 2 ) in nuts (peanuts and pistachios) was established. Under optimal conditions (35 mg F-COF, 100 mL sample solution, 3 mL min -1 as sample loading rate, pH<7, 0.2 mL acetonitrile as desorption solvent), the limits of detection for aflatoxins were 0.02-0.30 ng g -1 . The linear range was 0.08-16.0 ng g -1 and the recoveries of the F-COF-based method were 83.5-114 % with relative standard deviations less than 8.0 %., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Herein, two novel amino-functionalized triazine-based hyper-crosslinked porous polymer (NH 2 -HCPs) (named as DPT-BB, DPT-DX) were designed and synthesized by direct crosslinking of 2,4-diamino-6-phenyl-1,3,5-triazine (DPT) with 4,4'-bis(chloromethyl)-1,1'-biphenyl (BB) or α, α'-dichloro-p-xylene (DX). Thanks to the amino functional group and hyper-crosslinked porous structure, NH 2 -HCPs displayed remarkable adsorption ability for phenolic EDCs. The adsorption mechanism mainly involved hydrogen bond, π-π interaction, hydrophobic interaction and pore filling. Thus DPT-BB was applied as solid phase extraction sorbent to extract phenolic EDCs from water and orange juice samples prior to quantitative analysis by high performance liquid chromatography. Under the optimal conditions, detection limit as low as 0.07-0.2 ng mL -1 for water and 0.1-0.27 ng mL -1 for orange juice was achieved. Good recoveries spanned the range of 83.5%-114% were obtained for spiked samples, with relative standard deviations below 8.9%. The results demonstrated that the developed method displayed excellent practicability for sensitive analysis of EDCs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

A new method for spectrophotometric simultaneous determination of copper and mercury was developed by the dispersive liquid–liquid microextraction (DLLME) preconcentration and orthogonal signal correction–partial least squares (OSC–PLS). In the proposed method, dithizone was used as a chelating agent, and carbon tetrachloride and acetonitrile were selected as extraction and dispersive solvents. All factors affecting the sensitivity were optimized by the Box–Behnken design and the linear dynamic range for determination of copper and mercury was found. Under the optimum conditions, the calibration graphs were linear in the range of 10.0–250.0 and 10–300 ng mL−1 with detection limit of 2.6 and 2.8 ng mL−1 (3δB/m) and the enrichment factor of this method for copper and mercury, reached 180 and 175, respectively. The simultaneous determination of copper and mercury by using spectrophotometric methods is a difficult problem, due to the spectral interferences. The PLS modeling was used for the multivariate calibration of the spectrophotometric data. The OSC was used for preprocessing of data matrices and the prediction results of model, with and without using OSC, were statistically compared. The experimental calibration matrix was designed by measuring the absorbance over the range of 400–700 nm for 25 samples. The root mean squares error of prediction for copper and mercury with and without OSC was 0.010, 0.026 and 0.055, 0.086, respectively. The proposed method was successfully applied for the simultaneous determination of copper and mercury in spiked water and synthesis samples.

A separation–enrichment system based on adsorption of cadmium(II) and lead(II) ions as their 1-phenyl-1H-tetrazole-5-thiol chelates on Diaion SP-207 polymeric resin has been established. Flame atomic absorption spectrometry was used for the determination of cadmium and lead. Analytes were recovered (>95%) on 0.5 g Diaion SP-207 at pH 6.5 and 4.5 mg of 1-phenyl-1H-tetrazole-5-thiol at 1.5 ml min−1 flow rate. Cadmium and lead were desorbed by 10 ml of 1 M CH3COOH. The influences of some 1A and 2A group metals, transition metals on the recoveries of analyte were also investigated. Addition/recovery tests were performed. The accuracy was checked by the analysis of TMDA 54.4 fortified lake water certified reference material. The proposed procedure was applied for the analysis of analyte in real samples with successful results.

The core/shell Au@MnO 2 nanoparticles (Au@MnO 2 NPs) were prepared and characterized by UV-vis spectrum, transmission electron microscopy (TEM) and X-ray photoelectron spectrum (XPS). It was found that MnO 2 in the shell of Au@MnO 2 NPs could oxidize thiamine (VB 1 ) into blue fluorescent thiochrome (TC). The reduction of MnO 2 in the shell layer could lead to a decrease of Au@MnO 2 NPs size along with a blue shift of the localized surface plasmon resonance (LSPR) peak. Once ascorbic acid (AA) was introduced, MnO 2 in the shell was rapidly reduced to Mn 2+ ions. Accordingly, the oxidation of VB 1 was inhibited and the fluorescence of TC was weakened. Based on these phenomena, we have established a dual signal method for AA determination with the help of UV-vis and fluorescence spectrophotometer. Under the optimum conditions, the LSPR absorption peak shift (Δλ) of Au@MnO 2 NPs and the decrease in fluorescence of TC correlated well with AA concentration ranging from 0.75 to 17.5 μM. The detection limits of LSPR absorption assay and fluorescence assay were 0.18 and 0.47 μM, respectively. More importantly, this dual-signal detection method has been used for the determination of AA in vitamin C tablets with high accuracy and precision, indicating its promising potential applications., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

A simple high-performance liquid chromatography (HPLC) method coupled with an evaporative light scattering detector (ELSD) was developed for the determination of azithromycin in raw materials and pharmaceutical formulations (injections, capsules and tablets) without any pretreatment or derivatization step. Azithromycin, degradation products and formulation ingredients were separated efficiently by using the mobile phase consisted of ammonium acetate (0.05 M, pH 8.0) and acetonitrile (60:40, v/v) in an isocratic mode at 0.8 ml/min flow rate. Parameters of ELSD were 60 °C for evaporation temperature and 50 psi for pressure of carrier gas (air). A logarithmic calibration curve was obtained from 50.93 to 509.30 μg/ml (r = 0.9996) for azithromycin, with the limit of detection (LOD) of 6.75 μg/ml (S/n = 3) and the limit of quantification of 22.50 μg/ml (S/n = 10). The developed method was validated and applied with satisfactory accuracy and precision for the determination of azithromycin in raw materials and pharmaceutical formulations (recovery 99–102%, RSD

Unsymmetrical dimethylhydrazine (UDMH) is a widely used rocket propellant, which oxidizes to different compounds. The determination of UDMH transformation products in the environment is of great importance since many of them are highly toxic. Along with well-known transformation products, researchers report new compounds, and establishing their structures is difficult and may be unreliable, and data on their properties, such as toxicity, are often not available. Moreover, the available information on the existence of various UDMH transformation products is quite scattered, many compounds are mentioned in the literature only once and/or without satisfactory confirmation of the structure, and labeled as assumed compounds. All this complicates the identification of new UDMH transformation products and obfuscates the search for already known compounds. This review aimed to summarize and systematize the UDMH oxidation pathways and its transformation products. The attention was paid to in which environmental compartment or only in the laboratory study UDMH transformation products were detected, as well as their formation under conditions of combustion and generating by engines. Schemes for the transformation of confirmed UDMH products were summarized; required conditions for the relevant chemical reactions were described. A group of assumed UDMH transformation products - those substances found in contaminated compartments, but without full structure confirmation - is shown in a separate table. Data on the UDMH and its transformation products acute toxicity are presented. Predicting the transformation products properties, including acute toxicity, cannot be the primary determination method, as the results obtained often do not reflect real values and, when dealing with unknown substances, may lead to using false results. Improved understanding of the UDMH transformation pathways in environmental compartments potentially can lead to more accurate identification of new transformation products with future use in developing approaches to reduce the toxic effects of UDMH and its transformation products., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Endocrine disrupting chemicals (EDCs) pose a serious threat to human health even at extremely low concentration. Three carboxyl functionalized porous polymers (PDA-DPBP, PTCDA-DPBP and ODPA-DPBP) were synthesized for the first time and employed as solid-phase extraction sorbent to enrich phenolic EDCs at trace level. Compared with PTCDA-DPBP, ODPA-DPBP and corresponding carboxyl-free counterpart (PC-DPBP), PDA-DPBP delivered superior enrichment efficiency for the phenolic EDCs, which can be ascribed to the strong hydrogen bonding, pore filling, hydrophobic interaction and π-π interaction between PDA-DPBP and phenolic EDCs. Coupled with high performance liquid chromatography, phenolic EDC residues in bottled water, juice and milk samples were enriched and determined. At the optimum conditions, the PDA-DPBP based method provided a good linear response in the range of 0.04-100ng mL -1 for bottled water, 0.07-100ng mL -1 for juice and 0.15-500ng mL -1 for milk samples. The detection limits (S/N=3) were 0.01-0.04, 0.02-0.06 and 0.05-0.10ng mL -1 for bottled water, juice and milk, respectively. The method recoveries were in the range from 81.6% to 116%, with RSDs ≤ 7.7%. This work provides an attractive and reliable alternative method for sensitive determination of phenolic EDCs., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Background: Thyroid-stimulating hormone (TSH) is measured differently between diagnostic units using different devices, which makes cross-comparisons challenging. Here, we have developed a mathematical algorithm to harmonize TSH measurements between 2 instruments, the Abbott ISR2000 and the Siemens ADVIA Centaur XP., Methods: Applying the principle of the maximum allowable error between the standard curve and real signal values, the minimum number of comparison samples required for TSH hormone detection was calculated for both instruments. Next, a mathematical algorithm describing the relationship between TSH standard curves from both instruments was established. The algorithm was then tested on sample measurements from both instruments, with signals transformed to Siemens ADVIA Centuar XP-type data. Finally, test results were assessed where the relative error was 1/2 TEa). After algorithmic transformation, the average percentage error was reduced to 7.93% (<1/2 TEa)., Conclusions: Our algorithm enables TSH measurements across different instruments to be comparable, and provides a method to harmonize TSH data between laboratories that utilize different instrumentation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

A multi-walled carbon nanotubes (MWCNTs) film coated glassy carbon electrode (GCE) was fabricated, and the electrochemical oxidation of resorcinol (RS) was studied in Britton–Robinson (BR) buffer (pH 6.0) using cyclic, square wave, and differential pulse voltammetry (CV, SWV, and DPV). The results revealed that the modified electrode shows an electrocatalytic activity toward the oxidation of RS by a marked enhancement in the current response in buffered solution. The oxidation of RS at this nano-structured film coated electrode was irreversible and diffusion-controlled. Under the optimum conditions, the anodic peak current showed a linear relation versus RS concentration in the range of 1.2 × 10−6 to 1.9 × 10−4 M with detection limits of 4.9 × 10−7 and 1.1 × 10−6 M (signal-to-noise = 3) for SWV and DPV, respectively. Moreover, the modified electrode demonstrated good reproducibility (RSD = 2.4%, n = 10) and long-term stability. This method has been applied to the determination of RS in wastewater, and the recoveries were from 93% to 104%.

A new and effective spectrophotometric method was developed for the determination of adrenaline in pharmaceutical preparations for control purposes. The condensation of Mannish reaction between 1 mol of adrenaline with new ligand, 5-benzimino-1,3,4-thiodiazole-2-thione (I) in the presence of 1 mol of p-formaldehyde as the condensing agent with 15–25 ml of dioxin as solvent took place. The precipitate yield was yellowish-brown colored. The new ligand was prepared by the Schiff base reaction of 5-amino-3-H, 1,3,4-thiodiazole-2-thione and 1 mol of benzaldehyde in 15 ml of ethanol as solvent and one drop of glacial acetic acid. The accuracy and precision of this method were determined by analyzed laboratory samples of adrenaline, the results show absolute error ranging from −0.22 to +0.86 and relative errors ranging from ±1.4% to 8.6%. The calibration graph was linear in the range of 2–20 mg l−1 for adrenaline with an S.D equal to 2.17%, and RSD of 2.76% (n = 5; Conc. = 80 mg l−1). This method was successfully applied for the adrenaline determination in commercial pharmaceutical injections for the quality control.

Abstract: The homeobox transcription factor WUSCHEL (WUS) plays a critical role in keeping the balance between the maintenance and differentiation of stem cell population in shoot and floral meristems of Arabidopsis thaliana. The corresponding gene SlWUS is yet to be characterized in tomato. In order to characterize SlWUS gene and its biological function, we cloned it from tomato and analyzed its structure. Tissue expression showed that the SlWUS highly expressed in tomato flower abscission zone. The overexpression of SlWUS in Arabidopsis could trigger undifferentiation of plant flower organ and indeterminacy of flower identity, suggesting that SlWUS maybe involved in flower structure development as well as flower organ identity. Taken together, our results indicated that the SlWUS plays an important role in flower abscission zone and plant organ shedding.

As a hydrolysis mediated drug in vivo, the pharmacokinetics of melphalan are highly variable in patients. Few methodologies could simultaneously measure the concentrations of melphalan and its hydrolyzed metabolites in plasma. The aim of this study was to develop a simple, rapid and sensitive liquid chromatography/tandem mass spectrometry (LC-MS/MS) method for simultaneous determination of melphalan and its hydrolyzed metabolites, monohydroxy melphalan (MOH melphalan) and dihydroxy melphalan (DOH melphalan). A simple protein precipitation was employed for sample preparation and melphalan-d8 was used as internal standard. Baseline separation of target analytes was achieved using an XSelect HSS T3 column (2.1 × 50 mm, 5 µm) with a gradient elution at a flow rate of 0.5 mL/min in 5 min. The monitored transitions were m/z 305.1 → 287.7 for melphalan, m/z 287.1 → 228.0 for MOH melphalan, m/z 269.3 → 251.8 for DOH melphalan, and m/z 313.1 → 295.7 for melphalan-d8. The method was fully validated in accordance with the FDA guideline. The calibration curves were established over the range of 5.22-5220 ng/mL for melphalan, 7.94-1588 ng/mL for MOH-melphalan, and 15.0-3000 ng/mL for DOH-melphalan with the regression coefficients greater than 0.99. The intra- and inter-day coefficients of variation for the analytes were ≤11.0% and all the biases were less than 8.3%. The method has been successfully applied to the quantification of melphalan and its metabolites in clinical plasma samples obtained from hematopoietic stem cell transplantation patients who received a dose of melphalan for pre-transplant conditioning., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

A new porphyrin-based sensing platform in hexadecyl trimethyl ammonium bromide (CTAB) microemulsion is developed for highly sensitive detection of theophylline. In this sensing system, the zinc-porphyrin-cinnamic acid conjugate (Zn-TPPCA) works as fluorescence probe while theophylline can decrease fluorescence intensity of the probe. Further studies indicate the linear relationship between the fluorescence quenching value and the concentration of theophylline within a given range. And the introduction of CTAB microemulsion can greatly enhance sensibility and stability of this detecting system and facilitate the detection of theophylline. On the basis above, a highly sensitive sensing platform for theophylline is created with a low limit of detection (LOD) of 0.0083 μg mL -1 under the optimal detection conditions. And further application of this method in determination of commercially available theophylline preparation shows excellent results. Subsequent studies on quenching mechanism indicate that static quenching appears between Zn-TPPCA and theophylline. Therefore, this work provides not only a highly sensitive method for determination of theophylline but also further evidence for creation of biosensors for drugs with porphyrin derivatives., (Copyright © 2022. Published by Elsevier B.V.)

Design and fabrication of functionalized hypercrosslinked polymers (HCPs) for enhancing their performance by using green renewable monomers has attracted considerable research interest. In this study, hydroxyl‑functional HCP (labeled as OHHCP) was prepared via the knitting method by applying natural naringenin as a monomer for the first time. Due to the good hydrophilicity and strong H-bonding ability, the OHHCP showed high extraction capacity for nitroimidazoles. Thus, it was successfully applied as a potent adsorbent for solid phase extraction of five nitroimidazoles in water, honey and chicken meat, followed by high-performance liquid chromatography-diode array detector analysis. At the optimized conditions, the limit of detections (S/N = 3) of the proposed method for water, honey and chicken samples were 0.02 - 0.06 ng mL -1 , 0.5 - 1.0 ng g - 1 and 0.8 - 1.0 ng g - 1 , respectively. The recoveries were 80.0 - 110%, and the relative standard deviations were below 10.0%. The OHHCP also displayed good application prospects for other organic compounds with H-bonding capability. This study highlights the facile preparation of OH-functionalized HCPs from renewable and natural resources as potent adsorbents for polar compounds., Competing Interests: Declaration of competing interest The authors declare no conflict of interest. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

In this study, a novel kapok fiber-supported liquid extraction (KF-SLE) method was developed for conveniently extracting analytes from oil samples. Natural kapok fiber without any pretreatment was directly used as an oil support medium. The extraction device was conveniently constructed by directly packing some kapok fibers into a syringe tube. Due to the fibrous property of the kapok fiber, no filter plate was needed. The cost of a KF-SLE device was as low as 0.5 CNY. The KF-SLE process was conveniently conducted using a simple three-step protocol: (1) the oil sample without any pretreatment including dilution was added directedly; (2) then, the oil-immiscible extractant was added; (3) after waiting a certain time for static extraction, the extractant was eluted out by pressing the kapok fibers with the syringe plunger. The extractant could be directly transferred for subsequent instrumental detection. For the feasibility and proof-of-concept study, the method was applied to quantify four synthetic flavor chemicals in edible oils. Satisfied quantification results were obtained with the correlation coefficient (R 2 ) being greater than 0.996, the relative recoveries ranging from 92.90% to 107.53% and intra- and inter-day RSDs being less than 7.56%. All in all, for the first time, the SLE technique was expanded to process oil samples and the method has the characteristics of low cost, environmental friendliness, high sample processing throughput and ease of automation, offering a promising approach for edible oil sample preparations., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier B.V.)

OBJETIVO: Apresentar os critérios diagnósticos de ambigüidade genital, a conduta médica inicial e a postura esperada do pediatra. FONTES DOS DADOS: Revisão de literatura científica por meio de artigos publicados no MEDLINE nos idiomas inglês e português, no período de 1990 a 2007 e na faixa etária pediátrica. SÍNTESE DOS DADOS: O pediatra tem papel fundamental na avaliação da ambigüidade genital, cujo objetivo é obter diagnóstico etiológico preciso no menor tempo possível para definição do sexo e estabelecimento dos procedimentos terapêuticos. Há critérios diagnósticos específicos, porém, de modo geral, uma genitália é ambígua sempre que houver dificuldade para se atribuir o sexo à criança. O pediatra deve informar à família que a definição do sexo dependerá de investigação laboratorial minuciosa, feita preferencialmente por equipe interdisciplinar em serviço terciário. O cariótipo 46,XX ou 46,XY não é suficiente para definir o sexo de criação, porém esse exame é fundamental para direcionar a investigação. Quando não houver gônadas palpáveis, a primeira hipótese deve ser hiperplasia adrenal congênita. Entre as outras causas, estão insensibilidade parcial a andrógenos, deficiência da enzima 5alfa-redutase, disgenesia gonadal parcial e hermafroditismo. A família deve receber apoio e informações durante todo o processo de avaliação, e sua participação é fundamental na decisão sobre o sexo de criação. CONCLUSÕES: Embora casos de ambigüidade genital sejam relativamente raros para o pediatra, este deve estar informado sobre o tema e a conduta adequada a tomar, pois freqüentemente será o responsável pela orientação inicial da família e pela ligação entre esta e a equipe interdisciplinar.OBJECTIVE: To present the diagnostic criteria of genital ambiguity, the initial medical management and the attitude expected of pediatricians. SOURCES: Review of the scientific literature in the form of articles indexed on MEDLINE, in English and Portuguese, published between 1990 and 2007 and dealing with the pediatric age group. SUMMARY OF THE FINDINGS: Pediatricians have a fundamental role to play in the assessment of genital ambiguity, the purpose of which is to arrive at an etiologic diagnosis in the shortest possible time in order to define the patient's sex and plan treatment. There are specific diagnostic criteria, but, in general, genitalia are ambiguous whenever there is difficulty in attributing gender to a child. The pediatrician should inform the patient's family that assignment of their child's sex will depend upon detailed laboratory investigations, preferably carried out by a multidisciplinary team at a tertiary service. The 46,XX or 46,XY karyotypes are not alone sufficient to define the gender of rearing, although the test is fundamental to guide the investigation. When there are no palpable gonads, the first hypothesis should be congenital adrenal hyperplasia. Other causes included partial androgen insensitivity, 5alpha-reductase deficiency, partial gonadal dysgenesis and hermaphroditism. The family should be provided with support and information throughout the assessment process, and their participation is fundamental in the decision of which gender to rear the child in. CONCLUSIONS: Although cases of genital ambiguity are relatively rare for pediatricians, they should be well-informed on the subject and the correct management of these conditions, since they will often be responsible for the initial guidance that families receive and for maintaining contact between them and the multidisciplinary team.