Key Laboratory of Eco-chemical Engineering, Ministry of Education, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao, PR China.
Biosens Bioelectron. 2010 Jan 15;25(5):1082-7. doi: 10.1016/j.bios.2009.09.034. Epub 2009 Oct 1.
An ultrasensitive chemiluminescence method based on the Au nanoparticles amplification for the quantitative detection of single-nucleotide polymorphisms (SNPs) in genomic DNA was accomplished by the DNA polymerase I (Klenow fragment)-induced coupling of the nucleotide-modified nanoparticle probe to the mutant sites of duplex DNA under the Watson-Crick base-pairing rule. The concentration of the one-base mutant DNA was determined by chemiluminescence (CL) detection of the cupric ions dissolved from the CuS nanoparticles (NPs) modified on the Au NPs. The incorporation of Au NPs in this method significantly enhanced the sensitivity because a single Au NP can be loaded with 77 CuS NPs through the link-age of an amidization reaction between mercaptoacetic acid on the surface of Au NPs and aminoethanethiol on the surface of CuS NPs. A preconcentration process of cupric ions performed by anodic stripping voltammetric (ASV) technology further increased the sensitivity of the design for about 10-fold. As a result of these two combined effects, this method could detect as low as 19 aM SNPs and the linear range for SNPs was from 8.0x10(-17) to 1.0x10(-14) M.
一种基于金纳米粒子放大的超灵敏化学发光法，通过 DNA 聚合酶 I（Klenow 片段）诱导核苷酸修饰的纳米粒子探针与双链 DNA 中的突变位点在沃森-克里克碱基配对规则下偶联，实现了对基因组 DNA 中单核苷酸多态性（SNP）的定量检测。通过检测从修饰在金纳米粒子上的 CuS 纳米粒子（NPs）中溶解的铜离子的化学发光（CL），可以确定单碱基突变 DNA 的浓度。由于通过金纳米粒子表面的巯基乙酸和 CuS 纳米粒子表面的乙二硫醇之间的酰胺化反应，单个金纳米粒子可以负载 77 个 CuS NPs，因此该方法中 Au NPs 的掺入显著提高了灵敏度。通过阳极溶出伏安法（ASV）技术进行的铜离子预浓缩过程进一步将设计的灵敏度提高了约 10 倍。由于这两种结合效应，该方法可以检测低至 19 aM 的 SNP，并且 SNP 的线性范围为 8.0x10(-17) 至 1.0x10(-14) M。
