Chitosan functionalized magnetic graphene oxide nanocomposite for the sensitive and effective determination of...

Chitosan functionalized magnetic graphene oxide nanocomposite (Fe₃O₄@SiO₂@CS/GO) was successfully fabricated via a facile amide reaction between chitosan and graphene oxide. A novel extraction method using Fe₃O₄@SiO₂@CS/GO as nanoadsorbent was developed and applied to the efficient extraction and determination of multiple alkaloids from the complex matrix. The composition and structure of the nanoadsorbent was systematically characterized by various techniques. The nanoadsorbent possesses performances of high efficiency, easy operation, superparamagnetism, environment friendly and economic feasibility. The adsorption mechanism for alkaloids included π-π electron-donor-acceptor interaction, cation-π interaction and hydrogen bonding. The principal parameters influencing extraction procedure such as adsorbent dosage, pH, adsorption time, desorption conditions and regeneration cycles were investigated and optimized. Under the optimized conditions, the method exhibited good linear dynamic range with correlation coefficient (r²) higher than 0.997 and the limit of detection (LOD) was among 0.016--0.092 μg kg^-1. Intra- and inter-day relative standard deviations (RSDs) were <10%. These results indicated that the developed method was successfully applied for simultaneous detection of alkaloids in hotpot. This study provided valuable guidance and effective method for the analysis of alkaloids in intricate interference system.