Search

Habenaira plantaginea belong to orchid family which is native to Asia. Members of this family are commonly famous for the cure of pain and inflammation. To date, no research was found on isolation of compounds from this plant for the treatment of inflammation and analgesia nor has been published to our knowledge. The purpose of this study was to evaluate an analgesic, anti-inflammatory and anti-oxidant activity of the isolated compound from the most potent chloroform sub-fraction and the isolated compounds form the habenaria plantaginea. Anti-inflammatory analgesic and antioxidant potential of the various chloroform sub-fractions and isolated compounds from the most potent sub-fraction (HP-1 & HP-1) were screened for their in vitro enzymatic assays. Furthermore, prior to in-vivo investigation, the isolated compounds were subjected for their toxicity study. The potent compound was then examined for acetic acid-induced writhing, hot plate test, carrageenan-induced inflammation assays. Further various phlogistic agents were used for the evaluation of mechanism. In the COX-2 inhibitory assay the chloroform sub fraction Cf-4 demonstrated excellent activity as compared to the other sub-fraction with 92.15% inhibition. The COX-2 enzyme make prostaglandins which are directly involved in inflammation. Likewise against 5-LOX the Cf-4 was the most potent sub-fraction with IC50 3.77 µg/mL. The 5-LOX catalyzes the biosynthesis of leukotrienes which is a group of lipid mediators of inflammation derived from arachidonic acid. Free radicals can induce inflammation through cellular damage while chronic inflammation generates a large number of free radicals, whose eventually lead to inflammation. In antioxidant assays the Cf-4 fraction was displayed excellent results against ABTS, DPPH and H2O2 free radical with 88.88, 77.44, and 65.52% inhibition at highest concentration. Likewise, the compound HP-1 demonstrated 88.81, 89.34 and 80.43% inhibition while compound HP-2 displayed 84.34, 91.52 and 82.34% inhibition against ABTS, DPPH and H2O2 free radical which were comparable to the standard drug ascorbic acid respectively. This study's findings validate the use of this species as traditional use. [ABSTRACT FROM AUTHOR]

An ultrasensitive dual-signal ratiometric electrochemical sensor was developed for creatinine detection utilizing silver nanoparticles (Ag) with intrinsic self-calibration afforded by iron-nickel bimetallic Prussian blue (FeNiPBA) analogues. The Ag@FeNiPBA exhibits two redox signals corresponding to the Ag+/Ag and Fe3+/Fe2+ systems. Adding chloride (Cl−) solution increases the anodic current of the Ag/Ag system significantly due to the formation of silver chloride through solid-state electrochemistry. While the anodic current of the Ag/Ag system decreases in the presence of creatinine due to the competitive reaction, the Fe/Fe system's anodic current remains the same, which enables a ratiometric response. Under optimized conditions, the response ratio (IAg/IFe) decreases while the creatinine concentration increases linearly between 0.015 and 140 μM, with 0.004 μM as a good detection limit (S/N = 3). These results demonstrate superior performance over previously reported methods for electrochemical creatinine determination. The high sensitivity arises from the signal amplification of the Ag/AgCl solid-state electrochemistry, while the selectivity originates from the specific interaction between Ag+ and creatinine. The Ag@FeNiPBA hybrid can quantify creatinine in real samples with good recoveries. This work opens up new opportunities for applying dual-signal nanostructures to develop electrochemical sensors for (bio)molecule detection. [ABSTRACT FROM AUTHOR]

Industrial sectors are main responsible for continually releasing of harmful compounds in the form of wastewater. The potential utilization of bio-waste materials has received great attention to minimize the serious environmental issues. Therefore, the present research is focused to develop an Elaeis guineensis/polyvinyl alcohol/carbon nanotube (EG/PVA/CNT) composite via a simple polymerization method and tested to remove the dye from aqueous solutions. Field emission scanning electron microscopy (FE-SEM) and Fourier transform infrared spectroscopy (FTIR) characterizations were selected to confirm the morphology and chemical structures of composites. The water content measurement and swelling characteristics of EG/PVA/CNT were also elaborated. The evaluation of composites was explored through the elimination of methylene blue (MB) in a batch adsorption scheme including EG loading, pH of MB aqueous solutions, contact time, initial concentration of MB solutions, adsorbent dose and solution temperature. The results revealed that EG-based adsorbents have superior adsorption efficiency of 92.44%. The adsorption kinetics was well explained by pseudo-second-order model, while in adsorption isotherms, Langmuir model was appropriate to demonstrate the MB adsorption data giving superlative removal aptitudes. The thermodynamic results revealed that adsorption onto EG/PVA/CNT was favorable, spontaneous and exothermic in nature, while activation energy informed the physical type of adsorption process. The adsorption mechanism of MB onto EG/PVA/CNT was also proposed. Moreover, EG/PVA/CNT was in stable form with good adsorption capacity and could easily be recycled. Based upon the present research, a strong strategy between EG, CNT and PVA could successfully develop an economical adsorbent for the treatment of different effluents. [ABSTRACT FROM AUTHOR]

A sensitive and selective molecular imprinted polymeric network (MIP) electrochemical sensor is proposed for the determination of anti-cancer drug oxaliplatin (OXAL). The polymeric network [poly(pyrrole)] was electrodeposited on a glassy carbon electrode (GCE) modified with silver nanoparticles (Ag) functionalized Cu-metal organic framework (Cu-BDC) and nitrogen-doped carbon nanotubes (N-CNTs). The MIP-Ag@Cu-BDC /N-CNTs/GCE showed an observable reduction peak at −0.14 V, which corresponds to the Cu-BDC reduction. This peak increased and decreased by eluting and rebinding of OXAL, respectively. The binding constant between OXAL and Cu-BDC was calculated to be 3.5 ± 0.1 × 107 mol−1 L. The electrochemical signal (∆i) increased with increasing OXAL concentration in the range 0.056–200 ng mL−1 with a limit of detection (LOD, S/N = 3) of 0.016 ng mL−1. The combination of N-CNTs and Ag@Cu-BDC improves both the conductivity and the anchoring sites for binding the polymer film on the surface of the electrode. The MIP-based electrochemical sensor offered outstanding sensitivity, selectivity, reproducibility, and stability. The MIP-Ag@Cu-BDC /N-CNTs/GCE was applied to determine OXAL in pharmaceutical injections, human plasma, and urine samples with good recoveries (97.5–105%) and acceptable relative standard deviations (RSDs = 1.8–3.2%). Factors affecting fabrication of MIP and OXAL determination were optimized using standard orthogonal design using L25 (56) matrix. This MIP based electrochemical sensor opens a new venue for the fabrication of other similar sensors and biosensors. [ABSTRACT FROM AUTHOR]

An innovative electrochemical sensor was proposed for simultaneous determination of mycophenolate mofetil (Mph) and tacrolimus (TAC) for the first time. A novel sensor based on electro-polymerization of multi-walled carbon nanotubes (MWCNTs) and a novel Cu-1N-allyl-2-(2,5-dimethoxyphenyl)-4,5-diphenyl-1H-imidazole metal organic framework (Cu-ADPPI MOF) on disposable pencil graphite electrode (dPGE). Many techniques were used to characterize the electrochemical activity and surface structure of the fabricated sensor. The proposed sensor exhibited good catalytic performance towards Mph and TAC oxidation due to the synergistic effect. Under optimal conditions, the proposed sensor has achieved a linear range of 0.85–155 × 10−8 M and 1.1–170.0 × 10−8 M with LODs of 0.28 × 10−8 M and 0.36 × 10−8 M for Mph and TAC, respectively. The designated sensor showed good reproducibility, repeatability, stability, and selectivity for the determination of Mph and TAC. Moreover, the simultaneous determination of Mph and TAC in different human biological fluids was carried out with acceptable results. As a result, the proposed sensor opens a new venue for the use of electro-polymerized MOFs in combination with other conductive materials such as MWCNTs for electrochemical sensing of different analytes with the desired sensitivity and selectivity. [ABSTRACT FROM AUTHOR]

B Author Correction: Microchimica Acta (2023) 190:156 b https://doi.org/10.1007/s00604-023-05730-1 In this article the affiliation details of "Khalid Alhazzani" and "A. Z. Alanazi" were incorrectly given as "Department of Pharmacology, College of Medicine, Al Imam Mohammad Ibn Saud Islamic University, Riyadh, Saudi Arabia". It should have been "Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia" Publisher's note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. [Extracted from the article]

B Correction: Microchimica Acta (2021) 188:124 b https://doi.org/10.1007/s00604-021-04781-6 In this article the affiliation details for "Ali Mohammed Alaseem" and "Mohammad M. Algahtani" were incorrectly given as "Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia" and "Pharmacology department, College of Medicine, Al Imam Mohammad Ibn Saud Islamic University, Riyadh, Saudi Arabia". It should have been "Department of Pharmacology, College of Medicine, Al Imam Mohammad Ibn Saud Islamic University, Riyadh,Saudi Arabia" and "Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia" The original article has been corrected. [Extracted from the article]

An innovative electrochemical nanoprobe was developed for determination of vortioxetine (VORT), a serotonergic antidepressant drug, for the first time. The fabrication of the nanoprobe is based on decoration of a glassy carbon electrode with three-dimensional nickel ferrite nanospheres modified activated graphite nanoplatelets (3D NiFe2O4 NS/AGNP/GCE). The morphological characterization of the nanoprobe was carried out via scanning electron microscope (SEM), transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, energy dispersive X-ray spectroscopy (EDS), N2-adsorption-desorption isotherm, and powder X-ray spectroscopy (PXRD). In addition, the electrochemical behavior of the nanoprobe was described using cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). A well-defined and irreversible peak at 0.82 V was seen at the surface of 3D NiFe2O4 NS/AGNP/GCE. The proposed nanoprobe exhibited outstanding electro-catalytic activity towards VORT oxidation. Under the optimized conditions, the anodic oxidation currents were linearly proportional to VORT concentration at the working range 1.8–90 nM with a LOD of 0.55 nM. The nanoprobe was used to determine VORT in pharmaceutical tablets and human plasma samples. Satisfactory recoveries and RSD percentages were obtained in the range 103.8–107.7% (RSD% = 2.7–3.1%) and 101.4–105.3% (RSD % = 2.8–3.4%) for tablets and plasma samples, respectively. Moreover, the method was used to monitor VORT during a pharmacokinetic study in human volunteers with satisfactory results. The 3D NiFe2O4 NS/AGNP/GCE shows excellent sensitivity, reproducibility, and selectivity towards VORT detection. The proposed electrode could be utilized as simple, rapid, and inexpensive sensing tool for routine analysis and during pharmacokinetic/pharmacodynamic investigations. [ABSTRACT FROM AUTHOR]

A molecularly imprinted polymer (MIP) was developed for the electrochemical determination of the antiviral drug sofosbuvir (SOF). The MIP was obtained by polymerization of p-aminothiophenol (p-ATP) on N,S co-doped graphene quantum dots (N,S@GQDs) in the presence of gold nanoparticles to form gold-sulfur covalent network. The presence of quantum dots improves the electron transfer rate, enhances surface activity and amplifies the signal. The nanocomposites were characterized by FTIR, TEM, EDX, and SEM. The electrochemical performance of the electrode was investigated by differential pulse voltammetry and cyclic voltammetry. The sensor uses hexacyanoferrate as the redox probe and is best operated at a potential of around 0.36 V vs. Ag/AgCl. It has a linear response over the concentration range of 1–400 nM SOF, with a detection limit of 0.36 nM. Other features include high selectivity, good reproducibility and temporal stability. The sensor was applied to the determination of SOF in spiked human plasma. [ABSTRACT FROM AUTHOR]