Multiplex signal cascade fluorescent biosensing for single nucleotide
polymorphisms enhanced detection
Abstract
Glioma seriously endangers human lives and health, and precise SNPs
genotyping is the key to modern clinical theranostics. A single nucleic
acid signal amplification strategy cannot effectively ensure sensitivity
and specificity detection. Herein, a multiplex signal amplification
platform based on collaborative chain reaction (LCR, HCR) and cascaded
rolling circle reaction (RCA) was first presented for specific and
sensitive single nucleotide polymorphisms (SNPs) enhanced genotyping.
The elongation HCR products were G-quadruplex and enriched on the
magnetic nanoparticles (MBs). As the fluorescent intercalator, the
thioflavin T (ThT) ligand was significantly embedded G-quadruplex
structure for fluorescence enhancement, to indicate the mutation
occurrence. Making use of the multiplex signal amplification strategy,
as low as 1×10 -17 mol/L mutated strands can be
detected, and the allele frequency determined was accurately achieved at
0.5%, indicating high sensitivity and high fidelity. Furthermore, this
portable LCR-HCR-RCA multiplex signal cascade fluorescent biosensing
(LHRCA) was combined with the efficient enrichment and rapid separation
of magnetic nanoparticles (MBs), and suitable for glioma cell lysate
samples analysis, making it a promising candidate for disease-associated
SNPs discrimination.