Cd~(2+), Cu~(2+), Pb~(2+), Sr~(2+), and Y~(3+) binding characteristics of 17β-estradiol molecularly imprinted polymer particles incorporated with dicyclohexano-18-crown-6 for urine bioassay

摘要

The metal ion binding characteristics of molecularly imprinted polymer (MIP) submicron particles prepared using 17β-estradiol (E2) as a template, and incorporated with dicyclohexano-18-crown-6 (DCH18C6), were studied using differential pulse anodic stripping voltammetry. When Sr~(2+) was added to DCH18C6-E2-MIP particles already occupied by Cd~(2+), Cu ~(2+), and Pb~(2+) inside the binding sites, a displacement reaction was observed: Cd~(2+)/Cu~(2+)/Pb~(2+)-DCH18C6- E2-MIP + Sr~(2+) = Sr~(2+)-DCH18C6-E2-MIP + Cd ~(2+)/Cu~(2+)/Pb~(2+). This demonstrated that DCH18C6 had stronger binding affinity for Sr~(2+) than Cd~(2+) Cu ~(2+) or Pb~(2+). Strong DCH18C6 binding affinity was also observed for Y~(3+). Atomic emission spectrometry showed that DCH18C6-E2-MIP particles (150 mg/mL) resulted in 52% binding of Sr~(2+) (2000 ppm, at pH 6.3 ± 0.1 and ionic strength of 0.1M NaNO_2).