An Extraction Method for Determination of 6-Benzyladenine in Bean Sprout by Graphene Oxide/Polypyrrole Composite Adsorbent

A simple method for the isolation and determination of 6-benzyladenine (6-BA) in bean sprout based on graphene oxide/polypyrrole (GO/ppy) as the adsorbent of pipette-tip solid-phase extraction coupled with high-performance liquid chromatography was developed. GO/ppy composite was synthesized with graphene oxide and polypyrrole by in situ polymerization and characterized by scanning electron microscopy. The prepared GO/ppy has an ideal foamy appearance which not only maintained the lamellar structure of graphene but also showed less agglomeration. The parameter of mass ratio of GO/ppy in the preparation procedure and parameters of the extraction procedure including the amount of adsorbent and types and volumes of washing solvent and elution solvent were optimized to achieve optimal extraction efficiency. Good linearity of GO/ppy was achieved in the range of 44–2200 ng g −1 with correlation coefficient ( r ) of 0.9998. Recoveries between 92.5 and 103.7% were obtained at three spiked levels with RSDs ≤ 3.0%. The proposed method was successfully applied for the extraction and determination of 6-BA in bean sprout samples.