This invention discloses a ratiometric
DNA electrochemical sensor for
genotyping of wobbly base pairs, characterized by the innovative use of a non-specific amplification strategy (
ligase chain reaction, LCR) and the higher amplification efficiency and dominant role of Watson base pairs (GC, AT) compared to wobbly base pairs (GT, AC). Using alleles as target genes, and based on the Watson
base pair complementarity principle, two LCRs (LCRs) are designed. Fc→G and LCR MB→A
Ferrocene (Fc) and
methylene blue (MB), electroactive indicators with stable
detection performance in clinical samples, were selected as the
electrochemical response signals for the two LCRs, and their current ratio (IL) was used. MB / I Fc As the output
signal for
allele typing, finally, based on I... MB / I Fc Regional division enables precise determination of swing-type
base pair allele genotyping (homozygous
wild type, homozygous
mutant type, heterozygous type).