Beijing National Laboratory for Molecular Sciences, Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China.
Anal Bioanal Chem. 2011 Jun;400(7):2085-91. doi: 10.1007/s00216-011-4943-1. Epub 2011 Apr 5.
We developed a new simple and sensitive assay for lysozyme based on gold nanoparticle plasmon resonance light scattering (PRLS) measurement and naked-eye detection using for the first time the lysozyme DNA aptamer as the recognition element. Lysozyme DNA aptamer could stabilize gold nanoparticles (AuNPs) at high ionic strength. Introducing lysozyme to the system easily triggered the aggregation of AuNPs, producing a red-to-blue color change of the solution, red-shifted plasmon absorption, and enhanced plasmon resonance light scattering. The linear range was found to be 0.2∼4 nM for 0.7 nM AuNPs, 0.3∼6 nM for 1.4 nM AuNPs and 0.6∼8 nM for 2.1 nM AuNPs. About 0.1 nM lysozyme can produce an observable enhancement of PRLS signal. For visual detection, 1 nM lysozyme can produce a very distinctive color change. Satisfactory recoveries were obtained for simulated saliva and diluted urine samples, indicating that the method has potential for analyses of clinical samples. The simplicity and high sensitivity that are consistent with the resources and needs of many laboratories makes this method a good choice for routine analysis.
我们开发了一种新的基于金纳米粒子等离子体共振光散射（PRLS）测量和裸眼检测的溶菌酶的简单而灵敏的测定法，首次将溶菌酶 DNA 适体用作识别元件。溶菌酶 DNA 适体能在高离子强度下稳定金纳米粒子（AuNPs）。向体系中引入溶菌酶很容易引发 AuNPs 的聚集，产生溶液的颜色从红色到蓝色的变化、等离子体吸收的红移和等离子体共振光散射的增强。对于 0.7 nM 的 AuNPs，线性范围为 0.2∼4 nM；对于 1.4 nM 的 AuNPs，线性范围为 0.3∼6 nM；对于 2.1 nM 的 AuNPs，线性范围为 0.6∼8 nM。约 0.1 nM 的溶菌酶就能产生可观测到的 PRLS 信号增强。对于目视检测，1 nM 的溶菌酶就能产生非常明显的颜色变化。对于模拟唾液和稀释尿液样本，均获得了令人满意的回收率，表明该方法具有分析临床样本的潜力。该方法简单、灵敏度高，符合许多实验室的资源和需求，是常规分析的良好选择。
