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sults indicated that the present method is useful for selecting the most effective candidates from various antibody drugs from the point of view of binding forces between antibodies and living cells.Herein, we have reported a new one-step potentiometric immunoassay for the sensitive and specific detection of human plasma cardiac troponin I (cTnI), a biomarker of cardio-cerebrovascular diseases. Initially, the cTnI biomolecules were immobilized on the surface of a gold nanoparticle-functionalized screen-printed graphite electrode (SPGE). Thereafter, rabbit polyclonal antibodies to cTnI were covalently conjugated to the bis-MPA-COOH dendrimers through typical carbodiimide coupling. [https://www.selleckchem.com/products/rocaglamide.html Selleck Rocaglamide] The introduction of the target analyte caused a competitive immunoreaction between the immobilized cTnI on the electrode and the conjugated antibody on the dendrimers. The potentiometric measurement was mainly derived from the change in the surface charge on the surface of the modified electrode due to the negatively charged bis-MPA-COOH dendrimers after the immunoreaction. On increasing target cTcI, the number of charged dendrimers on the immunosensor decreased, resulting in a change in the electric potential. Under optimum conditions, the potentiometric immunosensor exhibited good potentiometric responses for the detection of cTcI and allowed the determination of the target analyte at a concentration as low as 7.3 pg mL-1. An intermediate precision of ≤8.7% was accomplished with batch-to-batch identification. Meanwhile, the potentiometric immunosensor showed good anti-interfering capacity and selectivity against other proteins and biomarkers. Importantly, our system displayed high accuracy for the analysis of human plasma serum samples containing target cTcI relative to commercial human cTcI enzyme-linked immunosorbent assay (ELISA) kits.In the pharmaceutical industry, finding cost-effective and real-time analyzers that provide valid data is a good aim. The purpose of this work was to propose a link between the pharmaceutical industry and the recent innovations in solid-contact ion-selective electrodes (SC-ISEs) for the utilization of these electrodes as real-time analyzers to evaluate the concentration of tetrahydrozoline HCl in different matrices. The backbone of these new potentiometric sensors is the conjunction of calix[6]arene and (2-hydroxypropyl)-β-cyclodextrin as molecular recognition elements and a network of multi-walled carbon nanotubes as a solid transducer material between an ionophore-doped PVC membrane and microfabricated Cu electrodes. The proposed sensors were optimized to determine tetrahydrozoline, and their performances were assessed according to the IUPAC recommendations. The proposed solid-contact sensors were compared with liquid contact sensors, and the former sensors were found to be better than the latter sensors in terms of durability, handling, and easier adaptation to industry with comparable sensitivity. The measurements were implemented using phosphate buffer (pH 6). The best obtained linearity range was 1 × 10-2 to 1 × 10-7 M, and the best LOD was 1 × 10-8 M. The sensors with the best performance were successfully applied to determine tetrahydrozoline in a pharmaceutical eye preparation and rabbit tears. The obtained results were statistically compared to those obtained by the official method of analysis, and no significant difference was obtained. The eco-score of the method was assessed using the eco-scale tool and also compared with that of the official method. The proposed approach was validated according to the International Council for Harmonisation (ICH) guidelines.This study proposes a new multi-residue enantioselective method for the determination of emerging drug contaminants in sea water by solid phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). To achieve satisfactory enantiomeric separation with a vancomycin stationary phase it was essential to limit sodium chloride in extracted samples to less then 1 μg per injection. This was achieved through a straightforward SPE method using a 50 mL water wash volume and analyte elution in acetonitrile. A Chiral-V enantioselective column (150 × 2.1 mm; 2.7 μm particle size) operated in polar ionic mode enabled simultaneous drug separations in 30 minutes. Analytes with enantioresolution ≥1 were the stimulants amphetamine and methamphetamine, the beta-agonist salbutamol, the beta-blockers propranolol, sotalol and acebutolol, the anti-depressants fluoxetine, venlafaxine, desmethylvenlafaxine and citalopram, and the antihistamine chlorpheniramine. Method quantitation limits were less then 10 ng L-1 and method trueness was 80-110% for most analytes. The method was applied to samples from the Forth and Clyde estuaries, Scotland. Chiral drugs were present at concentrations in the range 4-159 ng L-1 and several were in non-racemic form (enantiomeric fraction ≠ 0.50) demonstrating enantiomer enrichment. This emphasises the need for further enantiospecific drug exposure and effect studies in the marine environment.In this work, a magnetic material (Fe3O4-NH2@MIL-101) was successfully prepared, and the material was used as a sorbent for the magnetic solid-phase extraction (MSPE) of trace level monohydroxy polycyclic aromatic hydrocarbons (OH-PAHs) from urine samples for the first time. The target analytes were quantified by high performance liquid chromatography coupled with fluorescence detection (HPLC-FLD). The MSPE key factors, which include the amount of adsorbent, extraction time, pH, the effect of salt, eluting solutions and eluant volume, were systematically optimized. Under the optimized conditions, the developed method showed good linearity (0.03-200 ng mL-1), low limits of detection (0.016-0.042 ng mL-1, signal-to-noise ratio = 3) and satisfactory repeatability (relative standard deviation ≤ 10.1%, n = 5). The method showed stable average recoveries ranging from 78.3% to 112.9% and the enrichment factors were 9 to 15. Besides the satisfactory method parameters, the total MPSE process could be completed in no more than 5 minutes. These results indicated that Fe3O4-NH2@MOF based MSPE was a simple, efficient and fast method which was suitable for MSPE of OH-PAHs from urine samples.