Application of Gd2ZnMnO6/ZnO nanocomposite for electrochemical measurement of acetaminophen, diphenhydramine, and phenylephrine.

An electrochemical sensor with high sensitivity was designed and used to measure several drugs, including acetaminophen (AC), diphenhydramine (DPH), and phenylephrine (PHE). This sensor was created using a carbon paste electrode (CPE) that has been modified with a Gd2ZnMnO6/ZnO nanocomposite. In order to analyze the developed sensor, scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FT-IR) techniques were used. The electrochemical behavior of the modified electrode was investigated by cyclic voltammetry, chronoamperometry, and apparent resistance spectroscopy methods. Also, the compound's diffusion coefficient (D) was calculated. By using the differential pulse voltammetry, AC, DPH, and PA were determined with detection limits of 2.5 × 10-8, 3.3 × 10-8, and 1.4 × 10-8 M in the linear concentration ranges of 0.09-900 µM. Finally, the designed sensor was utilized to measure the drug in real samples, and acceptable results were obtained.

Determination of methotrexate in plasma and environmental samples using an electrochemical sensor modified by UiO66-NH2/mesoporous carbon nitride composite and synergistic signal amplification with decorated AuNPs.

Electrochemical methods have low toxicity, fast response and, easy operation. By modifying electrochemical sensors with a conductive and porous modifier, their sensitivity and selectivity can be improved. Nanomaterials with new and extraordinary properties are a new approach in science and especially in electrochemical sensors. In this study, UiO66-NH2/mesoporous carbon nitride (M - C3N4) composite provides a porous structure for decorated Au nanoparticles (AuNPs) to prepare a potent modifier for carbon paste electrode (CPE). Due to environmental toxicity of methotrexate, its sensitive, fast and, low-cost determination in workplace environments is of great interest. So, the modified CPE was applied as a sensitivity analysis approach for methotrexate in plasma samples. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used as techniques to optimize the analysis and measurement of methotrexate. To measure this drug, several effective parameters were optimized and a calibration curve was drawn under optimal conditions. The calibration curve showed a linear range from 0.5 to 150 µM with a detection limit of 0.15 µM for methotrexate. Examining the repeatability of the response of one electrode and multiple electrodes under optimal conditions shows the high precision of the developed method. Finally, this developed method based on UiO66-NH2/M-gC3N4/AuNPs|CPE was used to determine the methotrexate in the plasma sample using the standard addition method.

Application of the C-C3N4/Li2CoMn3O8//IL nanocomposite for design a sensitive electrochemical sensor inorder to detection of cetirizine, acetaminophen and phenylephrine in biological and pharmaceuticals samples.

Due to the side effects of cetirizine overdose and the need to monitor its concentration in the human body, in this work, an electrochemical sensor has been prepared by utilizing a carbon paste electrode modified with Li2CoMn3O8/CC3N4 nanocomposite and ethyl-3-methyl-imidazolium chloride ionic liquid ([EMIM][Cl]) to determine cetirizine in the human blood serum sample and urine as well as drug samples. Li2CoMn3O8/CC3N4 nanocomposite was characterized by Fourier transform infrared (FT-IR), field emission scanning electron microscope (FESEM), and X-ray diffraction (XRD) analysis. The investigation of the influence of each modifier component showed that the existence of all components in modification has a synergistic effect. Li2CoMn3O8/CC3N4/IL nanocomposite has a larger surface area relative to the components alone, thus providing a more fine-grained media to facilitate electron transfer during the reaction between analyte and electrode. Determination of cetirizine was performed in phosphate buffer solution with pH 7.0 and detection limits obtained in the concentration ranges of 0.03-0.9 and 3-300 µM was 11.8 × 10-9 M. The diffusion coefficient (D = 9.2 × 10-6 cm2s-1) of cetirizine at the surface of the modified electrode was determined by chronoamperometry. Finally, simultaneous detection of cetirizine, phenylephrine and acetaminophen was performed using the suggested sensor without any interference.

Fabrication of a sensitive sensor for electrochemical detection of diltiazem in presence of methyldopa.

Diltiazem (DTZ) is one of the most important drugs in blood pressure that is used to treat cardiovascular diseases. With this overuse of this drug and its use for suicide, swelling and neck cramps and fever has made it important to measure it. So, this paper will give an account of modification of carbon paste electrode with the ternary-nanocomposite including reduced-graphene oxide (rGO), cadmium oxide and 1-ethyl 3- methyl imidazole chloride as ionic liquid for using the determination of DTZ in blood serum samples. Characterization of the synthesized rGO, cadmium oxide, and modified electrodes and their electrochemical performance were studied by, scanning electron microscopy, and X-ray diffraction, electrochemical impedance spectroscopy, and voltammetry technique. The improvement of the DTZ oxidation current by modified electrode originated from the increased electrode surface area. The optimized method was validated and the results showed that LOD = 3 nM and good linearity. Also, a linear concentration range of 0.01-150 µM with a LOD of 0.03 µM in presence methyldopa were achieved based on the electrochemical investigations. The prepared sensor showed good repeatability (RSD = 2.26%) and selectivity for DTZ determination in the real samples (relative recovery of 93-102%).

Introducing of Li2FeMn3O8 /C-C3N4 /IL nanocomposite for electrochemical determination of pantoprazole sodium in real samples.

A new electrochemical sensor based on Li2FeMn3O8/C-C3N4 (LFMO/CCN)/1-ethyl-3-methylimidazolium chloride modified carbon paste electrode (CPE) has been constructed to measure pantoprazole sodium (PNZS). The electrochemical impedance spectroscopy (EIS) method was employed to evaluate the electrode charge-transfer resistances. Moreover, the differential pulse voltammetry method was used to detect PNZS in phosphate buffer solution (PBS) at pH 7.0. The detection limit of 80.0 × 10-9 M and 10.9 × 10-7 M was obtained under optimal conditions in the linear concentration range of PNZS 0.09-100 µM and 100-900 µM. Chronoampermetry technique was utilized to determine the diffusion coefficient (D) of PNZS on the modified electrode surface. The CCN/LFMO/IL/CPE was successfully used to determine PNZS in various drug formulations such as tablets and vials. Finally, simultaneous determination of PNZS and acetaminophen was accomplished with no interference based on the proposed sensor.