[Talanta] A DNAzyme sensor based on target-catalyzed hairpin assembly for enzyme-free and non-label
Single nucleotide polymorphisms (SNPs) are widely existed in human genome and associated with many diseases. Traditional PCR-based methods for SNP genotyping require protein enzyme, precise control of temperature and removal of resultant products, making the whole process labor intensive and time consuming. Although G-quadruplex DNAzyme-based assays provide many advantages over traditional approaches, the relatively low catalytic activity of DNAzyme becomes an unfavorable factor in its application process. Therefore, amplification of DNAzyme for further determination is of great desire in bioanalysis. In this work, we have developed an enzyme-free and non-label DNAzyme sensor for SNP genotyping based on target-catalyzed hairpin assembly (CHA) for DNAzyme amplification. The proposed sensor, carried out on microfluidic chemiluminescence (CL) assay, can sensitively discriminate rs242557 hotspot-SNP, the A/G single-nucleotide variation on human chromosome associated with Alzheimer's disease, with an absolute detection limit of 0.3 fmol.
Huiyan Xu, Qiwang Wu, Hong Shen, Institute of Microanalytical Systems, Department of Chemistry, Zhejiang University, Hangzhou 310058, China Received 28 November 2016, Revised 24 February 2017, Accepted 2 March 2017, Available online 6 March 2017