An Automated Method for the Determination of Diclofenac Sodium in Human Plasma

Abstract

An automated method utilizing laboratory robotics has been developed for quantifying diclofenac sodium concentrations in human plasma. The robotic system aliquots the biological sample, adds the internal standard (CGP 4287), extracts the compounds from the acidified biological matrix (pH less than 2) into an organic phase (hexane-isopropyl alcohol), and concentrates the extracts for reversed-phase, high-performance liquid chromatographic (HPLC) analysis. The laboratory robot is directly interfaced to the HPLC system, and the data are automatically collected and results calculated. Separation is achieved on a 3-microns ODS (6.2-mm x 8.0-cm) column with ultraviolet (UV) detection of the drug and internal standard at 280 nm. Recovery and reproducibility assessments indicate good accuracy (overall mean relative recovery of 99.8%) and precision (coefficient of variation from 0.5 to 11.1%) over the diclofenac sodium concentration range of 5.0-1000 ng/mL, with a quantification limit of 5.0 ng/mL. The method has been successfully applied to a pharmacokinetic study in which normal volunteers received 150 mg of a prototype controlled-release formulation of diclofenac sodium.

Pharmacokinetic study of diclophenac sodium in rat plasma by high-performance liquid chromatography

“…Identification and quantitative determination of DNa in the substance of DNa were carried out by most sensitive method of high-performance liquid chromatography [2,7,8,9,10]. This method was used to determine concentrations of the test substance at all stages of the study.…”

Residues of Diclofenac Sodium in Rabbit Tissues

“…Liquid chromatography operating conditions included diclofenac injection (20µL), with a flow rate of 1.2μL/min and UV -VIS detector adjustmentat276 nm. The chromatographic separation was performed using a mobile phase of 45% acetonitrile, 54.5% deionized water and 0.5% Ortho -phosphoric acid (v/v), pH 7.0 ± 0.1, at room temperature according to Brunner and Luders [14]. Measurement of residues in the examined samples was performed and determined from area under the curve (AUC), and appeared automatically by the software…”

Development of the method for quantitative determination of diclophenac sodium in rat plasma by high-performance liquid chromatography with regard to analysis characteristics of active substance micro-concentrations

“…Для визначення диклофенаку натрію в лікарських формах, а також в біологічних рідинах і органах людини існують наступні методи -рН-метричне титрування [11], газова хроматографія з мас-спектрометричним детектуванням [10,11], електрофорез і електрокінетична капілярна хроматографія [9,12], флуоресцентна спектроскопія [6], спектрофотометрія [7,8]. Однак більшість авторів визначали диклофенак у біологічних середовищах з використанням хроматографії.…”