Facile Synthesis of NiO/ZnO nanocomposite as an effective platform for electrochemical determination of carbamazepine.

The pharmaceutical science demand for sustainable and selective electrochemical sensors which exhibit ultrasensitive capabilities for the monitoring of different drugs. In an attempt to build a useful electrochemical sensor, we describe a most efficient method for the fabrication of NiO/ZnO nanocomposite through aqueous chemical growth method. The successfully synthesized NiO/ZnO nanocomposite is successfully employed to modify a glassy carbon electrode in order to build a sensitive and reliable electrochemical sensor for the detection of carbamazepine (CBZ), an anticonvulsant drug. The morphological texture, functionalities and crystalline structure of prepared nanocomposite were determined via FTIR, XRD, EDX, TEM, and SEM analysis. In order to examine the charge transfer kinetics, the cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to exploit the electrochemical properties of the synthesized nanocomposite. The NiO/ZnO nanocomposite exhibited excellent electron transfer kinetics and less resistive behavior than the individual NiO and ZnO nanoparticles. The differential pulse voltammetry and cyclic voltammetry tools were used for the fluent determination of CBZ. Certain parameters were optimized to develop an effective method including optimum scan rate 60 mV/s, potential range from 0.4 to 1.4 V and BRB as supporting electrolyte with pH 3. The developed sensor showed exceptional response for CBZ under the linear dynamic range from 5 to 100 µM. The limit of detection of proposed NiO/ZnO sensor for the CBZ was calculated to be 0.08 µM. The analytical approach of prepared electrochemical sensor was investigated in different pharmaceutical formulation with acceptable percent recoveries ranging from 96.7 to 98.6%.

Gas Chromatographic and Spectrophotometric Determination of Diclofenac Sodium, Ibuprofen, and Mefenamic Acid in Urine and Blood Samples.

OBJECTIVES: Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used for the treatment of acute to chronic pain. A simple, fast, and reliable gas chromatographic (GC) method with flame ionization detection has been developed for the determination of NSAIDs such as diclofenac sodium, ibuprofen, and mefenamic acid after derivatization with ethyl chloroformate. MATERIALS AND METHODS: The GC conditions were optimized as elution from a DB-1 column (30 mx0.32 mm id) at column temperature 150 °C for 3 min, followed by a heating rate of 20 °C/min up to 280 °C and a hold time of 5 min. The nitrogen flow rate was 2.5 mL/min. For spectrophotometric studies, the absorbance was measured against methanol at a wavelength of 200-500 nm. RESULTS: The calibration curves were linear within 2-10 µg/mL with limits of detection of 0.4-0.6 µg/mL of each drug. The derivatization elution, separation, and quantitation were repeatable (n=3) with relative standard deviation (RSD) within 3.9%. The method was applied for the analysis of the drugs from pharmaceutical formulations and the results of the analysis agreed with labeled values with RSDs within 0.5-3.9%. The results were also confirmed by standard addition method. The percent recovery was calculated with spiked deproteinized human blood serum and urine samples and % recovery of the drugs was obtained within 96-98% with RSDs within 3.1%. CONCLUSION: The validated method proved its ability for the assay of NSAIDs in bulk and dosage form in a short analysis time. The method was also useful for the analysis of biological samples.