RESUMO
The technique of solid phase micro-extraction (SPME) is an important method for sample pretreatment in analytical chemistry, especially for the analysis in micro-systems. Surface enhanced Raman scattering (SERS) is an ultra-sensitive and fast detection technique. Both are particularly important in qualitative analysis of trace amount of substance. In this study, combining the magnetic nanoparticles with magnetic SPME device, we develop a high efficient new pretreatment method named as disperse magnetic solid phase micro-extraction (Dis-MSPME). In comparison to the traditional SPME, the proposed Dis-MSPME realizes solid phase micro-extraction from dispersive system, which improved the extraction efficiency largely. Conjunction the advantages both of Dis-MSPME and SERS is proposed as Dis-MSPME-SERS as a new detection method, which realize enrichment, magnetic separation and detection all-in-one. Making it a simpler, more efficient and sensitive approach in identifying the illegal additives. Sildenafil citrate (SC) in 500µL health wine as an example of illegal additive was successfully detected in a LOD of 1.0 × 10-8M. Moreover, comparative study on the extract efficient of Dis-MSPME-SERS with SPME-SERS shows it takes only 10min to detect sildenafil citrate in the health wine, from enrichment to detection by Dis-MSPME-SERS.