Ion-Pair Chromatography for Simultaneous Analysis of Ethionamide and Pyrazinamide from Their Porous Microparticles

Abstract

Abstract. Ethionamide (ETA) and pyrazinamide (PZA) are considered the drugs of choice for the treatment of multidrug-resistant tuberculosis. Current methods available in the literature for simultaneous determination of ETA and PZA have low sensitivity or involve column modifications with lipophilic cations. The aim of this study was to develop a simple and validated reversed-phase ion-pair HPLC method for simultaneous determination of ETA and PZA for the characterization of polymeric-based porous inhalable microparticles in in vitro and spiked human serum samples. Chromatographic separation was achieved on a Phenomenex C 18 column (250 mm×4.6 mm) using a Shimadzu LC 10 series HPLC. The mobile phase consisted of A: 0.01% trifluoroacetic acid in distilled water and B: ACN/MeOH at 1:1 v/v. Gradient elution was run at a flow rate of 1.5 mL/min and a fixed UV wavelength of 280 nm. The validation characteristics included accuracy, precision, linearity, analytical range, and specificity. Calibration curves at seven levels for ETA and PZA were linear in the analytical range of 0.1-3.0 μg/mL with correlation coefficient of r 2 >0.999. Accuracy for both ETA and PZA ranged from 94 to 106% at all quality control (QC) standards. The method was precise with relative standard deviation less than 2% at all QC levels. Limits of quantitation for ETA and PZA were 50 and 70 ng/mL, respectively. There was no interference from either the polymeric matrix ions or the biological matrix in the analysis of ETA and PZA.

Combination therapy for tuberculosis treatment: pulmonary administration of ethionamide and booster co-loaded nanoparticles

“…For instance, booster molecules do not have sufficient water solubility for in vivo efficacy (below mg/mL) 16 and have low affinity for most of the biodegradable materials used to prepare NPs. ETH was already encapsulated in colloidal systems 17 , microparticles 18 , 19 and PLGA NPs 20 . However, the strong tendency of ETH to crystallize in aqueous environments as well as in biological fluids makes its incorporation in a nanocarrier particularly difficult 20 .…”

Development and validation of simple and sensitive HPLC-UV method for ethambutol hydrochloride detection following transdermal application

“…14 Ion-pair chromatography is able to increase the affinity of charged analytes to the stationary phase, thus improving the peak shape and retention time of the solutes. 15 However, such HPLC methods are typically associated with inconsistent results, due to the separation of the ion-pairs during HPLC analysis, thus limiting its utility in both formulation evaluation and biological analysis. 16 Therefore, the utilisation of a precolumn derivatisation method offers the advantage of enhancing the sensitivity, selectivity and separation behaviour of the analyte of interest relative to ion-pair chromatography.…”

Design of imprinting matrix for dual template sensing via electropolymerized polythiophene films

“…Both AnP and ETH have been individually detected via many chemical analysis methods such as spectrophotometric methods, gas liquid chromatography (GLC), high-performance liquid chromatography (HPLC) and fluorometry. [25][26][27][28][29][30][31] However, compared with these methods, the electrochemical methods are of low cost, facile, rapid methodology, real time results, sensitive and environment friendly. [32][33][34] Furthermore, molecular imprinting is advantageous due to high selectivity, negligible matrix effect, high adsorption performance, good stability, and reusability.…”

“…Both AnP and ETH have been individually detected via many chemical analysis methods such as spectrophotometric methods, gas liquid chromatography (GLC), high‐performance liquid chromatography (HPLC) and fluorometry 25‐31 . However, compared with these methods, the electrochemical methods are of low cost, facile, rapid methodology, real time results, sensitive and environment friendly 32‐34 .…”