Centrifugal dynamic hybridization conducted in a microfluidic chip for signal enhancement in nucleic acid tests

Abstract

A rotating platform has been developed using a centrifugal chip holder to mount the standard chips for liquid delivery achieved by centrifugal pumping. This platform allows for dynamic hybridization to be performed in the microchannels constructed in the standard chips made using the 50 mm × 75 mm glass slides which allows for fast hybridization reactions. The results show that when the oligonucleotide-oligonucleotide hybridization is performed, there is good differentiation between perfectly complementary strands over 1 bp-mismatching counterparts when the long target strand is firstly immobilized and the short probe is secondly hybridized (Method 2), but not when the short probe is first immobilized, and the long target is subsequently hybridized (Method 1). When the differentiation between immobilized ginseng PCR product strands is performed, the correct result is achievable by Method 1, after signal enhancement and addition of formamide. The use of Method 2 is successful only when the PCR strand is captured, but not immobilized. In both methods, proper differentiation is achievable using the N1Q probe, un-achievable without centrifugal hybridization.