In-situ synthesis of carbon dots embedded wrinkled-mesoporous silica microspheres for efficiently capturing and monitoring organochlorine pesticides from water and fruit juice

Abstract

An in-situ synthesis strategy was proposed for fabrication of carbon dots embedded wrinkled mesoporous silica (CDs/WMS) microspheres. Characterizations results demonstrated that the doping of CDs with a moderate content still allowed the microspheres to maintain wrinkled and highly mesoporous structures. The CDs/WMS composite was subsequently employed as solid phase microextraction (SPME) coating for sensitive determination of ultra-trace organochlorine pesticides (OCPs) from aqueous solutions. High surface area, abundant chemical groups, and plentiful porosity made CDs/WMS microspheres present superior extraction capacities for OCPs compared with commercial SPME coatings and pure WMS. Under the optimum extraction conditions, the proposed analytical method exhibited wide linearity range (0.2–1000 ng/L), low detection of limits (0.0023–0.073 ng/L for water, 0.0062–0.41 ng/L for fruit juice), and satisfactory reproducibility with relative standard deviations of 6.2 %−13.3 % and 7.3 %−13.2 % for water and fruit juice, respectively. Finally, the proposed method was successfully used for determination of OCPs in real water and fruit juice samples. The recoveries varied from 80.1 % to 105.2 % for water and 71 % to 106.8 % for fruit juice. This study developed a novel strategy for synthesis of CDs/WMS microspheres, and proposed a new type of SPME coating, which expanded the potential of CDs in capturing organic pollutants from aqueous solutions.