Colorimetric Detection of Lead Ion Based on Gold Nanoparticles and Lead-Stabilized G-Quartet Formation

• 作者: Ping Chen Qifeng Jiang Ruiying Zhang Shixiong Deng Xingliang Xiong
• 来源期刊: 生物医学工程(英文)
• 学科: 化学
• 关键词: GOLD Nanoparticles G-Quartet PB2+ COLORIMETRIC Detection
• 年，卷（期）: 2015,（7）
• 页码范围: 451-457
• 页数: 7页
• 分类号: O6

摘要

In this report, we present a method for the detection of Pb2+ based on the different adsorption capacity on the surface of gold nanoparticles (AuNPs) between ssDNA (single-stranded DNA) and G-quartet. In the absence of Pb2+, the DNA oligonucleotides probe, which is guanine-rich ssDNA, can be adsorbed on the surface of AuNPs protecting them from aggregation. After adding Pb2+, the DNA oligonucleotides probe can specifically form compact G-quartet, which can induce the aggregation of unmodified AuNPs, especially after adding NaCl aqueous solution. Consequently, the color turns from red to blue. Pb2+ can be detected by colorimetric response of AuNPs;its detection limit can reach 5 μM only observed by naked eyes. Most metal ions have no interferences, and the interference of Cu2+ can be effectively eliminated by adding cysteine. It provides a simple and effective colorimetric sensor for on-site and real time detection of Pb2+.