title: Colorimetric detection of DNA sequences using an organic solvent to induce the aggregation of label-free gold nanoparticles.
abstract: A novel assay based on a solvent for inducing the aggregation of AuNPs colloid was proposed to discriminate ssDNA from dsDNA. Eleven organic solvents with different polarity were investigated, and it was found that DMSO was possible to aggregate AuNPs at the amount of only 0.4 microL in a 50-microL detection system. Further research showed that 0.8 microL of DMSO could discriminate the ssDNA from dsDNA. Colorimetric detection with various conditions, including the ratio of the target to the probe, and the concentration of AuNPs and DNA, was investigated. The proposed method was successfully used for SNP typing, and unambiguous discrimination of a wild type from a mutant was obtained for the templates with the mismatched base at the 5'-end or in the middle of the target sequence. As no requirement of gold modification and detection instrument, we believe that this method will be much low in the cost for DNA detection.
authors.affiliation: China Pharmaceutical University, Nanjing 210009, PR China.
authors.forename: Huning
authors.initials: H
authors.lastname: Jia
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Cao
authors.forename: Cong
authors.initials: C
authors.lastname: Fu
authors.forename: Jianping
authors.initials: J
authors.lastname: Wang
authors.forename: Zhiyao
authors.initials: Z
authors.lastname: Chen
authors.forename: Bingjie
authors.initials: B
authors.lastname: Zou
authors.forename: Li
authors.initials: L
authors.lastname: Jin
authors.forename: Zhengyu
authors.initials: Z
authors.lastname: Yan
authors.forename: Guohua
authors.initials: G
authors.lastname: Zhou
mesh_terms: D003124:Colorimetry / Q000379:methods*; D004247:DNA / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles; D009930:Organic Chemicals / Q000737:chemistry*; D020641:Polymorphism, Single Nucleotide; D012997:Solvents / Q000737:chemistry*
chemical_list: D009930:Organic Chemicals; D012997:Solvents; D006046:Gold; D004247:DNA