A rapid pretreatment of PVC products for high-throughput and visual detection of trace heavy metals

A novel method, based on modified silver nanoparticles, for high-throughput visual detection of heavy metal ions in polyvinyl chloride (PVC) products was developed including a key pretreatment process in which tetrahydrofuran was used to dissolve PVC powder samples quickly. Heavy metal ions were successfully transferred from THF to the aqueous phase by the liquid–liquid extraction method during the pretreatment procedures. Then, enriched Cu 2+ , Mn 2+ , and Cr 3+ were detected by three kinds of silver nanoparticles (4-MBA-AgNPs, 4-MBA-MA-AgNPs, and 4-NBT/4-MBA-AgNPs) using naked eyes and microplate reader, respectively. The visual detection limits of Cu 2+ , Mn 2+ , and Cr 3+ were 1.0 × 10 −6 M, 1.0 × 10 −7 M, and 1.0 × 10 −6 M, while the detection limits of Cu 2+ , Mn 2+ , and Cr 3+ were 2.5 × 10 −8 M, 5.0 × 10 −8 M, and 5.0 × 10 −8 M using microplate reader, respectively. Apparently, the proposed method could provide a potent means in the practical detection of heavy metal ions in PVC products with advantages of low-cost, rapid, high-throughput, and on-site detection. Graphic abstract