Development of miniaturized headspace solid phase extraction coupled with dispersive liquid-liquid microextraction for extraction and preconcentration of some residual solvents in several herbal medicines

Abstract

Introduction: Residual organic solvents are volatile organic chemicals left over from the process of manufacturing pharmaceuticals and formulation of pharmaceutical products, which cannot be completely removed from the final product during various processes, and their presence in the final product is not desirable and causes many problems.Objectives: The aim of this study is to develop a miniaturized headspace solid phase extraction coupled with dispersive liquid-liquid microextraction for extraction and preconcentration of some residual solvents in several herbal medicines by light and eutectic solvents. The extracted analytes are measured by GC-FID. Method: This research work was done with two different extraction solvents. In general, 0.7 g of the herbal medicine sample was inserted into the balloon of the extraction container blocked with a narrow tube containing the appropriate amount of absorbent, a mixture of water and ethylene glycol was added to the sample and placed on the heater under optimal conditions. Analytes adsorbed to the adsorbent surface were washed with DMF and then extracted into a few microliters of extracting solvent during the DLLME process.Results: Under optimal conditions, limits of detection and quantification in the first part were in the ranges of 0.59 to 0.94 and 1.9 to 3.1 and for the second part were in the ranges of 0.84 to 1.2 and 2.8 to 4.1 ng/g, respectively. Discussion and conclusion: According to the results, this method can be used as an applicable method for extraction, preconcentration, and determination of residual solvents in several herbal medicinal samples. Low LOD and LOQ, high EF and good repeatability are the important benefits of this study.