Direct RNA detection without nucleic acid purification and PCR

Direct RNA detection without nucleic acid purification and PCR: Combining sandwich hybridization with signal amplification based on branched hybridization chain reaction.

Xu Y1, Zheng Z2.

Biosens Bioelectron. 2016 May 15;79:593-9.
PMID: 26761615 DOI: 10.1016/j.bios.2015.12.057

Abstract
We have developed a convenient, robust and low-cost RNA detection system suitable for high-throughput applications. This system uses a highly specific sandwich hybridization to capture target RNA directly onto solid support, followed by on-site signal amplification via 2-dimensional, branched hybridizing chain polymerization through toehold-mediated strand displacement reaction. The assay uses SYBR Green to detect targets at concentrations as low as 1 pM, without involving nucleic acid purification or any enzymatic reaction, using ordinary oligonucleotides without modification or labeling. The system was demonstrated in the detection of malaria RNA in blood and GAPDH gene expression in cell lysate.