【摘要】 在pH7.4的Na₂HPO₄-NaH₂PO₄缓冲溶液及人绒毛膜促性腺激素多肽探针（HCGP）存在下,银纳米粒子（AgNPs）发生聚集;当加入人绒毛膜促性腺激素（HCG）后,形成稳定的HCGP-HCG复合物,AgNPs能够稳定地分散在溶液中。该多肽反应液中分散的AgNPs对H₂O₂还原HAuCl₄生成金纳米粒子的反应具有较强的催化作用,其产物金纳米微粒在550nm处有一较强的表面等离子体共振（SPR）吸收峰。随着HCG浓度增大,反应液中分散的AgNPs增加,催化作用增强,550nm处的吸光度增大。HCG浓度在0.5¹5μg/L与吸光度增大值ΔA_550nm成线性,检出限为0.2μg/L。据此,建立了简便、价廉、灵敏检测HCG的多肽探针纳米银催化光度新方法。更多还原

【Abstract】 In pH 7.4 Na₂HPO₄-NaH₂PO₄ buffer solution with the presence of human chorionic gonadotropin peptide（HCGP）probe,the AgNPs can be aggregated to bigger AgNPs clusters.However,AgNPs can be well dispersed into this solution when the human chorionic gonadotropin（HCG）is added to form stable HCGP-HCG composite.The well-dispersed AgNPs exhibits catalysis on the reaction of H₂O₂ reducting HAuCl₄ into AuNPs which appeares a strong surface plasmon resonance（SPR）peak at 550 nm.With the increase of HCG concentration,the SPR peak increases linearly at 550 nm.The increased SPR absorption(ΔA_{550 nm})is linear to HCG in the range of 0.25⁵0μg/L,with a regression equation of ΔA_{550 nm}=0.012 4 C+0.02,a correlation coefficient of 0.987 8,and a detection limit of 0.2 μg/L.Thus,a simple,low-cost and sensitive nanosilver-catalytic SPR spectrometry was developed for the determination of HCG.更多还原