Volume 43, Issue 1

In this work, a solid-state electrochemical sensor relying on potentiometric transduction was constructed and optimized to detect Bosentan (BOS) in its pharmaceutical dosage form and human plasma. BOS is useful in pulmonary hypertension management as a nonselective endothelin receptor antagonist. A printed circuit board has been constructed and used as a substrate for microfabricated Cu electrodes. In comparison to a microfabricated control (Cu/ISM) electrode, the sensor potential signal drift was enhanced, and the response time was reduced by using multi-walled carbon nanotubes (MWCNTs) as an ion-to-electron transducer layer. According to IUPAC requirements, the suggested BOS sensors have been electrochemically characterized, and the linear dynamic range is (1.0 × 10 −8 to 1.0 × 10 −5 ) M with a limit of detection of 6.28 × 10 −9 M and 6.12 × 10 −9 M for MWCNT-based sensor (Cu/CNT-NC/ISM) and control sensor (Cu/ISM), respectively. The described sensors have been used successfully to selectively determine BOS in dosage form and human plasma without any pre-treatment steps.

A green analytical chemistry study attempts to generate environmentally friendly alternatives to dangerous compounds while reducing waste output. The study thoroughly analyzed eight green tools to determine their greenness. Given its importance in treating hallucinations and delusions produced by Parkinson’s disease psychosis, it is critical to have a reliable and precise method for identifying pimavanserin (PVS) in both pure form and pharmaceutical formulations. The current study used a straightforward approach to forced degradation experiments to establish a novel reversed-phase high-performance liquid chromatography method for evaluating stability. The method was executed on the Agilent Zorbax Eclipse Plus C18 column (100 × 4.6 mm, 3.5 μm particle size) with ultraviolet detection at 226 nm. The Box–Behnken design is the ultimate solution for identifying optimal chromatographic conditions in a timely and efficient manner, with minimal trials required. The study investigated the impact of three factors: acetonitrile ratio, column oven temperature, and flow rate on various responses, namely, retention time, tailing factor, and theoretical plates. Desirability and overlay plots were utilized to forecast the best mobile phase containing a buffer solution: acetonitrile: tetrahydrofuran in a ratio of (65: 20: 15, v/v/v), which proved highly effective in the experiments. Linearity was conducted for PVS in the 3–50 µg·mL −1 range with an R 2 coefficient of determination of 0.9997. PVS had detection and quantification limits of 1.1 and 3.5 µg·mL −1 , respectively, indicating a highly significant correlation between the variables studied. PVS’s recovery percentage was determined to be 101.30%. We also used the Six Sigma lean technique to ensure precision and productivity. PVS was tested for acid, base, oxidative hydrolysis, photodegradation, and heat, as per International Council for Harmonisation guidelines. The highest degradation was obtained from oxidative hydrolysis and thermal degradation. Graphical abstract

Alkaloid enantiomers have different physiological and pharmacological effects, and different chiral compositions have a large impact on cigarette sensory and use safety. Studying the effects of different configurations of alkaloid enantiomers on cigarette sensory is important for the development of tobacco products, but the chiral separation of alkaloid enantiomers has become the core problem. Here, the application of a C18 column coupled with a polysaccharide-based chiral column to separate and detect four pairs of alkaloid enantiomers in tobacco and cigarette smoke of different brands was investigated. Results showed that the tandem technology of the two columns enabled the baseline separation of four pairs of alkaloid enantiomers. The resolution of enantiomers of alkaloids in different tobacco samples differed in content and ratio, showing different chiral distribution characteristics. According to the different distribution characteristics of alkaloid enantiomers, tobacco samples of different brands can be distinguished and real cigarettes can be identified.

Green chemistry and white chemistry are two approaches to chemistry that prioritize sustainability and environmental protection. The pursuit of green chemistry is to develop chemical processes and products that decrease or stop the use and generation of dangerous materials. In contrast, white chemistry focuses on developing energy-efficient, sustainable chemical processes that produce minimal waste. Our study evaluated the environmental friendliness of the suggested approach, using eight greenness appraisal techniques, including analytical eco-scale, analytical method volume intensity, HPLC-environmental assessment tool, analytical method greenness score, analytical greenness, analytical greenness metric for sample preparation, green analytical procedure index, and complexgreen analytical procedure index, in addition to the unique metric blue applicability grade index of white chemistry. We have developed and validated a highly effective and reliable method for concurrently analyzing designated pharmaceutical medications characterized in metformin (MET) and empagliflozin (EMP) formulations, including their degraded products. This method is cost-effective, specific, and environmentally friendly, utilizing reversed-phase high-performance liquid chromatography with an XBridge BEH C8 column (150 mm × 4.6 mm, 5 μm) at a flow rate of 1.0 mL·min −1 , an injection volume of 5.0 μL, a column oven temperature of 50°C, a wavelength of 224 nm, and a mobile phase comprised of phosphate buffer adjusted at pH 6.8 and acetonitrile in gradient mode. In the HPLC method, linearity has been achieved over the concentration range of 10–106 and 30–1,050 µg·mL −1 for EMP and MET, respectively, with correlation coefficients more than 0.999 and good recoveries within 98–102%. An assessment of the content uniformity of finished products confirmed that they met the declaration’s acceptance standards (85–115%). A comparative study has been successfully conducted on generic and reference products, demonstrating their similarity. The suggested approach was validated by adhering to international council for harmonisation criteria. Graphical abstract

Liquid chromatography-mass spectrometry (LC-MS) is a very sensitive technique for determining small concentrations of drugs in fixed dose combinations or even those deposited in skin layers. Therefore, an LC-MS method was applied for determining the drugs under investigation, namely, clioquinol (CLIO), tolnaftate (TOL), and betamethasone (BETA) in Quadriderm® cream and mixed lipid nanostructures (MLNs) prepared in laboratory in the presence of potential interferents, and was applied as a dermato-kinetic study in rat’s skin. The separation was achieved within 4.5 min by using C18 column as a stationary phase and the mobile phase used were 20% phase A composed of 0.1% formic acid (v/v) and 80% phase B composed of 0.1% formic acid in acetonitrile (v/v), coupled with triple quadrupole mass spectrometer. MLNs were prepared and characterized to be compared with the conventional commercially available Quadriderm® cream. The proposed method was accurate and precise with a linearity range of 0.2–20.0 µg·mL −1 for BETA, and 0.5–400.0 µg·mL −1 for CLIO and TOL and a better bioavailability of the new formulation was obtained ensuring the capability of the nanoparticles to accumulate the drugs within the skin layers. In conclusion, the LC-MS method was accurate and precise for the determination of the three drugs under investigation in cream dosage form and skin tissues.

Lung cancer has a high mortality rate largely due to late-stage diagnosis. Detecting protein and genetic biomarkers through electrochemical immunosensors enables non-invasive early diagnosis. This review discusses recent advances in electrochemical immunosensors for detecting clinically relevant lung cancer biomarkers. The use of nanomaterials like graphene, carbon nanotubes, metal nanoparticles, and conducting polymers in sensor fabrication improves electron transfer kinetics, enhances signal transduction, and allows higher antibody loading. Smart surface immobilization strategies optimize antibody orientation and binding capacity. Amplification approaches utilizing nanomaterials, enzymes, polymers, dendrimers, and DNA nanostructures are applied to enhance output signal per binding event. Various electroanalytical techniques including amperometry, potentiometry, impedance spectroscopy, and voltammetry are employed for quantitative monitoring. Recent immunosensors showcase low detection limits and wide linear ranges for measurement of major biomarkers like carcinoembryonic antigen, neuron specific enolase, and cytokeratin fragment 21-1. Emerging biomarkers such as microRNAs and circulating tumor cells have also been targeted. However, reproducibility, selectivity, multiplexing, and integration with point-of-care platforms need improvement for widespread clinical translation. Overall, electrochemical immunosensors hold immense potential for sensitive, affordable lung cancer diagnosis if ongoing efforts can address current limitations.

Graphical abstract Abstract The latest advances in honey trace contaminants analysis according to 70 articles gathered, mainly from the last 4 years, are critically reviewed, focusing on green and environmentally friendly aspects. Sample preparation protocols for multi-element analysis are slowly evolving towards green chemistry but older methods are still employed. Analytical methods are moving to mass spectrometry determinations, but other spectroscopic methods are also an answer. Dispersive sample preparation methods followed by chromatography coupled with tandem mass spectrometry proved their utility for multi-residue analysis of a wide array of trace organic compounds. Multiplex/multiclass methods development arises as a new field in honey contaminant analysis: They are greener than the traditional ones, as a bunch of families of chemical contaminants can be determined in a single extraction step. The regulatory framework did not follow the analytical procedures evolution. Honey is an animal-origin food, and contamination from other sources is seldom considered. The lack of holistic approaches from a legal point of view menaces public health as honey is consumed during the whole lifetime and hampers integrative analytical developments.

Clozapine (CLZ) has retained its clinical utility in the management of schizophrenia despite the discovery of novel antipsychotics, as it possesses unique efficacy in the setting of treatment resistant schizophrenia while causing minimal extrapyramidal symptoms. However, these benefits are offset by the risk of agranulocytosis and other side effects, and therapeutic drug monitoring (TDM) is routinely recommended for patients undergoing treatment with CLZ. A multitude of approaches for the quantification of CLZ have been developed for different settings such as TDM, quality control of pharmaceutical dosage forms, and toxicology studies. Primarily, these approaches fall under one of three branches of analysis, namely, chromatography, electrochemical analysis, and spectrophotometry. This study provides a scoping review of the recent advances in the methods of quantification for CLZ and highlights the potential utility of novel methods in the field of drug quantification.

Cationic surfactants (CSs) are surface-active compounds containing a positively charged polar group and at least one alkyl chain as a nonpolar group. Due to their structure, they tend to adsorb on negatively charged surfaces and interact with biopolyanions. It leads to their wide use as disinfectants, cleaning agents, fabric softeners, hair care products, emulsifiers, corrosion inhibitors, etc. Considering their extensive use and also their toxicity, fast, simple, and accurate CSs determination is crucial in industrial process control, product quality assurance, and environmental monitoring. Potentiometric sensors meet all these requirements, so they stand as the primary method for CSs determination. In this review, numerous potentiometric methods for CSs determination have been described, with a particular focus on methods published in the period from 2000 to 2024. Due to their simplicity and good analytical performance, solid-state electrodes are the most commonly used type of sensor for CSs determination. Graphical abstract

Surface-enhanced Raman spectroscopy (SERS) is a modern analytical technique that can be used to determine the structure and composition of analyzed specimens at the molecular level. This technique is also minimally invasive and destructive. This and other advantages of SERS against traditional techniques used in forensics make it the ideal method for the identification of bodily fluids, soil constituents, drugs and chemicals, and colorants on or in hair, fabric, and paints. In this article, we first introduce the reader to the fundamental physical properties of SERS. Next, we discuss the most recent findings that are focused on SERS-based analyses of physical evidence related to forensics research. Finally, we provide a critical overview of where the future of SERS should be in forensics science. Graphical abstract

Molecularly imprinted polymers (MIPs) as materials with determined levels of selectivity and specificity for designated analytes have recently gained much attention in various application fields. However, with the growing adoption of green analytical chemistry (GAC) principles, it is essential to investigate the greenness of MIP synthesis and its subsequent application in sample preparation, as well as to evaluate the “green” nature of the developed analytical methodologies, such as dispersive solid-phase microextraction (DSPME). Accordingly, the main objective of this research was to evaluate the greenness of MIP-based glycidyl methacrylate synthesis and MIP use as a DSPME sorbent prior to high-performance liquid chromatography with mass spectrometry (HPLC-MS). The green perspective of MIP-DSPME prior to HPLC-MS was investigated using various analytical metric tools such as the Analytical Eco-Scale, the Green Analytical Procedure Index, and Analytical GREEnness (AGREE). Since these analytical tools are not fully implementable for the assessment of the greenness of the MIP synthesis, some alternative approaches were used to optimize the synthesis parameters to make the MIP DSPME sorbent as close as possible to the GAC principles. The calculated AGREE score (0.62) and 91 points in the Analytical Eco-Scale for the proposed DSPME technique using MIP indicated a high level of greenness. Graphical abstract

This study aims to prefer the suitability of an analytical approach developed for simultaneously determining ciprofloxacin hydrochloride (CIP) and hydrocortisone (HYD) in their ear drop dosage form. The preference between the three known instruments was utilized, namely UV-spectrophotometry, reversed phase-high-performance liquid chromatography (RP-HPLC)-UV, and thin-layer chromatography (TLC)-densitometry. The instrumentational studies determined that the mathematical UV methods (utilized various manipulation designs such as the isoabsorptive point, absorbance ratio, extended ratio subtraction, ratio difference, and mean centering of ratio spectra) had linearities in the range of 2.0–14.0 and 1.0–14.0 µg·mL −1 , the RP-HPLC-UV method showed a linearity range of 1.0–8.0 µg·mL −1 , and the TLC-spectrodensitometric method had linearity ranges of 0.2–1.6 µg/band and 0.6–2.0 µg/band for both CIP and HYD, respectively. The analytical performance, validity, and greenness of the approaches were evaluated through the benchmarking of key performance indicator (KPI)-based standards and a SWOT (strengths, weaknesses, opportunities, and threats) analysis. The KPIs and SWOT study focused on several aspects, including (1) the selectivity and robustness of the methods, (2) sensitivity, (3) accuracy and precision, (4) applicability, (5) whiteness, (6) greenness, and (7) blueness. However, the assessment of whiteness, greenness, and blueness was conducted using well-known ecological assessment tools such as the RGB12 Algorithm, Analytical Eco-Scale, AGREE, GAPI, and Blue Applicability Grade Index. In conclusion, based on the findings, UV-spectrophotometry emerged as the most practically convenient approach. It demonstrated advantages based on the predetermined KPI-based standards. Furthermore, UV-spectrophotometry was deemed to be the most environmentally friendly option. Graphical abstract