纳米金核酸适配体共振瑞利散射光谱检测卡那霉素的研究

Resonance Rayleigh Scattering Spectral Detection of Kanamycin Using Gold Nanoparticles-Aptamer Complex

在pH 7.4的硼砂-硼酸缓冲溶液及NaCl存在下,纳米金与卡那霉素适配体可形成稳定的纳米金-核酸适配体复合物。而卡那霉素可与复合物中的适配体形成稳定的结构,并释放出纳米金,此时纳米金在NaCl作用下团聚成较大微粒,导致571 nm处的共振瑞利散射峰强度增强,据此建立了测定卡那霉素的新方法。考察了溶液pH值、NaCl浓度、反应时间、不同序列核酸适配体以及共存物质对测定的影响。在优化实验条件下,卡那霉素浓度在0.02～0.3 mg/L范围内与共振光强度（ΔI）呈良好的线性关系,相关系数（r）为0.995 6,方法检出限（3σ）为2.3μg/L。将该方法用于卡那霉素注射液中卡那霉素含量的测定,结果满意。

In pH 7. 4 borax-boric acid buffer solution and in the presence of NaCl,gold nanoparticles（ GNPs） interacted with kanamycin aptamer to form a stable nanogold-aptemer complex. When kanamycin was added in the solution,it could interact with the aptamer to form a more stable composite while GNPs were released. The uncombined GNPs aggregated into large clusters,which could cause the increase of resonance Rayleigh scattering（ RRS） intensity at 571 nm in high concentration of NaCl. Effects of pH value,NaCl concentration and reaction time on the resonance scattering intensity were studied. Moreover,influences of different aptamers and coexistent substances on the determination were also investigated. The results showed that the method had good selectivity. Under the optimum conditions,the increased RRS intensity was linear over kanamycin concentration range of 0. 02-0. 3 mg /L,with a correlation coefficient（ r） of 0. 995 6 and a detection limit（ 3σ） of 2. 3 μg /L. The method was applied in the determination of kanamycin in kanamycin injection with satisfactory results.