Development and Application of Chitosan Nanogel as a Sorbent for Methotrexate Extraction

Background: Successful drug extraction from biological fluids is challenging due to interfering factors and the trace levels of the target analytes. Objective: We aimed to provide a suitable and sensitive method to increase the efficiency of methotrexate extraction from biological fluids. Methods: Chitosan-based nanogel synthesized by the ionic gelation method was used for solidphase microextraction of methotrexate from aqueous and plasma media. The nanogel was characterized in vitro in terms of morphological characteristics (transmission electron microscopy), particle size, polydispersity index (PDI), and zeta potential. High-performance liquid chromatography was used to determine the methotrexate concentrations and extraction yield. Results: A nanogel with an average size of 135.6 nm and PDI of 0.14 was used for the nanoextraction of methotrexate in this study. The methotrexate concentration, nanogel amount, and extraction time affected the extraction yield. Maximum recovery percentages of 75% and 69% were achieved when extracting methotrexate from aqueous and plasma media, respectively. Conclusion: The high extraction yields in both studied media indicate that using chitosan-based nanogel as a sorbent during the solid-phase microextraction of methotrexate is a promising prospect, with potential uses for other drugs in different media. It seems that using nanogels can be an excellent way to improve the extraction of drugs from biological environments.