ADMET and DMPK最新文献

A simple and sensitive method for the determination of propranolol using a modified carbon paste electrode with graphene/Co₃O₄ nanocomposite was presented. The electrochemical measurements of propranolol are studied using differential pulse voltammetry, cyclic voltammetry and chronoamperometry. The graphene/Co₃O₄ nanocomposite exhibits excellent catalytic activity towards the electrochemical oxidation of propranolol in phosphate buffer solution of pH 7.0. The graphene/Co₃O₄ nanocomposite facilitates the determination of propranolol in the concentration range 1.0-300.0 μM and a detection limit and sensitivity of 0.3 μM. and 0.1275 μA/μM were achieved.

In this paper, the electrochemical behavior of hydrochlorothiazide (HCTZ) is described using carbon paste electrodes modified with polypyrrole nanotubes (PPy-NTs/CPEs) at pH value 7. Experiments revealed that the presence of HCTZ greatly impacts the electrochemical behavior of modified CPEs. The synthesized PPy-NTs were utilized as a sensing material for the electrochemical detection of HCTZ and were investigated by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and chronoamperometry. The key experiment conditions, including supporting electrolyte and electrolyte pH, were studied and optimized. Under optimized conditions, the prepared sensor displayed the linear relationships for the concentrations of HCTZ from 5.0 to 400.0 μM (R² = 0.9984). The detection limit of the PPy-NTs/CPEs sensor was found to be 1.5 μM using the DPV method. The PPy-NTs is highly selective, stable and sensitive for the determination of HCT. Therefore, we believe the newly prepared PPy-NTs material can be useful for different electrochemical applications.

The epithelial sodium channel (ENaC) is a transmembrane protein that regulates the balance of sodium salt levels in the body through its expression in various tissues. The increase in sodium salt in the body is related to the expression of ENaC, thereby increasing blood pressure. Therefore, overexpression of the ENaC protein can be used as a biomarker for hypertension. The detection of ENaC protein using anti-ENaC in the biosensor system has been optimized with the Box-Behnken experimental design. The steps carried out in this research are screen-printed carbon electrode modification with gold nanoparticles, then anti-ENaC was immobilized using cysteamine and glutaraldehyde. Optimum conditions of the experiment, such as anti-ENaC concentration, glutaraldehyde incubation time, and anti-ENaC incubation time, were optimized using the Box-Behnken experimental design to determine the factors that influence the increase in immunosensor current response and the optimum conditions obtained were then applied to variations in ENaC protein concentrations. The optimum experimental conditions for anti-ENaC concentration were 2.5 μg/mL, the glutaraldehyde incubation time was 30 minutes, and the anti-ENaC incubation time was 90 minutes. The developed electrochemical immunosensor has a detection limit of 0.0372 ng/mL and a quantification limit of 0.124 ng/mL for the ENaC protein concentration range of 0.09375 to 1.0 ng/mL. Thus, the immunosensor generated from this study can be used to measure the concentration of normal urine samples and those of patients with hypertension.

Tramadol is a centrally-acting analgesic used for treating moderate to severe acute and chronic pain. Pain is an unpleasant sensation that occurs most commonly as a result of tissue injury. Tramadol possesses agonist actions at the μ-opioid receptor and effects reuptake at the noradrenergic and serotonergic systems. In the last years, several analytical procedures have been published in the literature for the determination of tramadol from pharmaceutical formulations and biological matrices. Electrochemical methods have attracted tremendous attention for the quantification of this drug owing to their demonstrated potential for quick response, real-time measurements, elevated selectivity and sensitivity. In this review, we highlighted the recent advances and applications of nanomaterials-based electrochemical sensors for the analysis and detection of tramadol, which is extremely important for the indication of effective diagnoses and for quality control analyses in order to protect human health. Also, the main challenges in developing nanomaterials-based electrochemical sensors for the determination of tramadol will be discussed. At last, this review offers prospects for the future research and development needed for modified electrode sensing technology for the detection of tramadol.

We report the synthesis, structural characterization and pharmaceutical activity of four coumarin-quinone hybrids. The compounds were significantly active against Staphylococcus aureus, Pseudomonas aeoginosa and Candida albicans. Promising antioxidant activity was observed when compared to ascorbic acid. Two compounds, DTBSB and DTBSN, also showed commendable in vitro antiproliferative activities against the cells of human cancer cell lines MCF-7, MDA-MB-231, COLO-205, HT-29 and A549 along with appreciable tumor selectivity with distinct selectivity index. Molecular docking studies using cyclooxygenase-2 (PDB ID: 6COX) revealed strong binding affinities for the COX-2 active site. Moreover, ADMET properties of the synthesized compounds were determined using the pKCSM and SwissADME online tools and all the compounds had accurate pharmacokinetic profiles. Hence, the new coumarin-quinone hybrids DTBSB and DTBSN can be considered for optimization and lead development.

Chitosan-coated magnetite nanoparticles (Chitosan@Fe₃O₄) were used to modify the carbon paste electrode (Chitosan@Fe₃O₄/CPE) to enhance sensitivity for salicylic acid (SA) analysis using square wave voltammetry (SWV). The performance and behaviour of the purposed electrodes were investigated using cyclic voltammetry (CV). The results showed that the mixed behaviour process was observed. Furthermore, parameters affecting SWV were also studied. It was discovered that the optimum conditions were a two-linearity range of SA determination, 1-100 and 100-400 μM. The limit of detection (LOD) and the limit of quantitation (LOQ) for SA are 0.57 μM and 0.90 μM, respectively. The proposed electrodes were successfully used to determine SA in applications employing pharmaceutical samples.

The zinc ferrite nano-particles (ZnFe₂O₄) modified screen-printed graphite electrode (ZnFe₂O₄/SPGE) was used for the voltammetric determination of vitamin B₆ in real samples, using differential pulse voltammetry (DPV). It has been found that the oxidation of vitamin B₆ at the surface of such an electrode occurs at a potential about 150 mV less positive compared to an unmodified screen-printed graphite electrode. After optimization, a vitamin B6 sensor with a linear range from 0.8 to 585.0 μM and a detection limit of 0.17 μM. The ZnFe₂O₄/SPGE sensor exhibits good resolution between the voltammetric peaks of vitamin B₆ and vitamin C, making it suitable for detecting vitamin B₆ in the presence of vitamin C in real samples.

The possibility of detection and determination of flavonoids by using microbial cells was shown for the first time using the quercetin - Azospirillum baldaniorum Sp245 model system. The activity of the flavonoids quercetin, rutin and naringenin toward A. baldaniorum Sp245 was evaluated. It was found that when the quercetin concentration ranged from 50 to 100 μM, the number of bacterial cells decreased. Rutin and naringenin did not affect bacterial numbers. Quercetin at 100 μM increased bacterial impedance by 60 %. Under the effect of quercetin, the magnitude of the electro-optical signal from cells decreased by 75 %, as compared with the no-quercetin control. Our data show the possibility of developing sensor-based systems for the detection and determination of flavonoids.

The Electronic tongue (ET) has been used as a diagnostic technique in the medical sector. It is composed of a multisensor array set with high cross-sensitivity and low selectivity characteristics. The research investigated using Astree II Alpha MOS ET to determine the limit of early detection and diagnosis of food-borne human pathogenic bacteria and to recognize unknown bacterial samples relying on pre-stored models. Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC25922) were proliferated in nutrient broth (NB) medium with original inoculum (approximately 107*10⁵ CFU/mL). They were diluted up to 10^-14 and the dilutions ranging from 10^-14 to 10^-4 were measured using ET. The partial least square (PLS) regression model detected the limit of detection (LOD) of the concentration that was monitored to grow the bacteria with different incubation periods (from 4 to 24 h). The measured data were analysed by principal component analysis (PCA) and followed by projecting unknown bacterial samples (at specific concentrations and time of incubation) to examine the recognition ability of the ET. Astree II ET was able to track bacterial proliferation and metabolic changes in the media at very low concentrations (between the dilutions 10^-11 and 10^-10 for both bacteria). S.aureus was detected after 6 h incubation period and between 6 and 8 h for E.coli. After creating the strains' models, ET was also able to classify unknown samples according to their foot-printing characteristics in the media (S.aureus, E.coli or neither of them). The results considered ET a powerful potentiometric tool for the early identification of food-borne microorganisms in their native state within a complex system to save patients' lives.

A new mononuclear Co(II) complex with the formula [Co(HL)2Cl2] (1) (HL= N-(2-hydroxy-1-naphthylidene)-2-methyl aniline) has been synthesized and characterized by Fourier transform infrared spectroscopy, UV-Vis, elemental analysis and single crystal X-ray structure analysis. Single crystals of the complex [Co(HL)2Cl2] (1) were obtained through slow evaporation of an acetonitrile solution at room temperature. The crystal structure analysis revealed that the two Schiff base ligands create a tetrahedral geometry via oxygen atoms and two chloride atoms. The nano-size of [Co(HL)2Cl2] (2) have been synthesized by the sonochemical process. Characterization of nanoparticles (2) was carried out via X-ray powder diffraction (XRD), scanning electron microscopy (SEM), UV-Vis, and FT-IR spectroscopy. The average sample size synthesized via the sonochemical method was approximately 56 nm. In this work, a simple sensor based on a glassy carbon electrode modified with [Co(HL)2Cl2] nano-complex was developed ([Co(HL)2Cl2] nano-complex/GCE) for convenient and fast electrochemical detection of butylated hydroxyanisole (BHA). The modified electrode offers considerably improved voltammetric sensitivity toward BHA compared to the bare electrode. Applying linear differential pulse voltammetry, a good linear relationship of the oxidation peak current with respect to concentrations of BHA across the range of 0.5-150 μM and a detection limit of 0.12 μM was achieved. The [Co(HL)2Cl2] nano-complex/GCE sensor was applied to the determination of BHA in real samples successfully.