Dispersive micro-solid phase extraction of tebuconazole residues from orange juice using a graphene oxide-silica...

Tebuconazole is a widely used triazole fungicide that poses health risks and is environmentally persistent, necessitating sensitive analytical methods for monitoring. This study developed a dispersive micro-solid-phase extraction (D-μSPE) method using graphene oxide-silica functionalized with 1-vinyl-3-hexylimidazolium octane sulfonate (GO@Si-[VHIm]⁺OS^-) for tebuconazole determination in orange juice by HPLC-MS/MS. The optimized protocol used 5 mg of sorbent dispersed in 1 mL of sample for 10 min, followed by desorption with 100 μL of a CPME:MeOH mixture. Method validation demonstrated excellent linearity (50-900 ng mL^-1, r² = 0.9972), satisfactory precision (RSD ≤9.4%), recoveries of 98-117%, and an LOQ of 0.19 ng mL^-1. The sorbent showed successful reusability over four consecutive extraction cycles (RSD of 8.0%). Green chemistry assessment tools, ComplexMoGAPI and BAGI, yielded favorable scores of 71% and 65 points, respectively, confirming the method's environmental sustainability. This approach offers a promising eco-friendly analytical protocol for monitoring tebuconazole residues in complex food matrices.