基于在pH 8.0的Tris-盐酸缓冲溶液中,由于腺苷的诱导使被十六烷基三甲基溴化铵包盖的金-银复合纳米粒子(Au-AgNPs)聚集,并引起在波长600 nm处其局域表面等离子体共振散射(LSPRS)的强度发生变化,而且此共振散射强度的变化值与腺苷的浓度在0.50~90 μmol·L-1范围内呈线性关系,其检出限(3σ)为0.02 μmol·L-1。据此,提出了新的测定北虫草中腺苷含量的共振散射光谱法(RSS)。对腺苷与Au-AgNPs之间的诱导聚集反应的试验条件作了优化,并通过透射电子显微镜和同步光散射光谱法对Au-AgNPs的聚集情况作了表征。所提出的方法已应用于测定北虫草中腺苷的含量,并用标准加入法计算得方法的回收率在96.0%~100%之间,测定值的相对标准偏差(n=5)均小于5.5%。

Based on the fact that aggregation of Au-Ag compound nanoparticles (Au-AgNPs) capped with CTMAB were induced by the reaction with adenosine in a Tris-HCl buffer solution of pH 8.0, thus leading to variation of intensity of local surface plasma resonance scattering (LSPRS) at the wavelength of 600 nm; and then the extents of the variation of intensity of LSPRS were found to keep linear relationship with the values of concentration of adenosine in the range of 0.50-90 μmol·L-1, with detection limit (3σ) of 0.02 μmol·L-1, a new method of resonance scattering spectroscopy was proposed for the determination of adenosine in Cordyceps militaris. The experimental conditions of the induced aggregation reaction between Au-AgNPs and adenosine were optimized and the aggregation of Au-AgNPs was characterized by transmission electron microscope and synchronous light scattering spectroscopy. The proposed method was applied to the determination of adenosine in samples of Cordyceps militaris, and values of recovery found by the method of standard addition were ranged from 96.0%-100%, with values of RSD′s (n=5) less than 5.5%.