A novel environmental pollutant thiophanate-methyl fungicide detection in milk samples by quartz crystal microbalance nanosensor based on molecularly imprinting polymer and sulfur-doped reduced graphene oxide nanomaterial
摘要
The purpose of this study was the development of a sensitive quartz crystal microbalance sensor based on a sulfur-doped reduced graphene oxide nanomaterial and molecularly imprinting polymer for thiophanate-methyl determination in milk samples. For this aim, the sulfur-doped reduced graphene oxide nanomaterial was firstly prepared by using a facile Hummers method with a high product yield. Then, a thiophanate-methyl–imprinted quartz crystal microbalance chip based on sulfur-doped reduced graphene oxide was accomplished by UV polymerization by the mixture including N,N′-azobisisobutyronitrile as an initiator, ethylene glycol dimethacrylate as a cross-linker, and methacryloylamidoglutamic acid as a monomer. The spectroscopic and microscopic methods were applied to confirm the presence of the nanocomposite and the reliability of the sensor preparation procedure. As a result, the prepared quartz crystal microbalance sensor exhibited linearity in the range 1.0 × 10−9–1.0 × 10−8 M with a detection limit of 3.3 × 10−10 M in milk samples. A quartz crystal microbalance technique with high sensitivity, selectivity, repeatability, reusability, and reproducibility was prepared for thiophanate-methyl determination in this study.
Graphical Abstract