Solid-phase extraction and liquid-liquid extraction are the most routine and classical extraction methods used in laboratories; however, a large number of published papers have focused on the development of microextraction techniques. The mass and volume of the extraction phase are the main differences between the classical extraction and the microextraction techniques. Among different sample preparation procedures, sorptive extraction (SE) techniques have widely been used for the extraction of different organic compounds [1]. Thin film microextraction (TFME) was developed by Pawliszyn et.al. It utilizes a sheet of flat membrane with high surface area-to-volume ratio as extraction phase [2]. In comparison to solid phase microextraction (SPME) technique,
TFME has higher analytical sensitivity with shorter extraction time due to the increase in available surface area and extractive phase volume. In this study, the applicability of graphene oxide/arginine (GO/Arg) mixed matrix membrane (MMM) for thin film microextraction (TFME) is reported for the first time. The GO/Arg MMM was used as sorbent for the thin film microextraction (TFME) of uric acid as model compound. The prepared GO/Arg composite has been incorporated into a mechanically stable polyvinylidene difluoride (PVDF) membrane. The contribution of GO sheets in the prepared film significantly improved the extraction efficiency of the sorbent. After the extraction, elution step was performed with organic solvent. Thereafter, the desorbed analyte was quantified by high performance liquid chromatography-ultraviolet detection (HPLC-UV). A Plackett–Burman design was used for screening the experimental factors of interest and specify the significant variables affecting the extraction efficiency. The effective factors were optimized using
Box-Behnken design (BBD). Finally, the applicability of the method was investigated by the extraction and determination of uric acid in different biological fluids including urine and plasma samples.