Fabrication of 3-D gel microarrays directly with raw polymerase chain reaction products by heat-directed polymerization

In this study, a new method for fabricating 3-D polyacrylamide gel microarrays was presented. In the method, a 3-D gel microarray was successfully fabricated by directly heating the slides with arrayed prepolymer at 80 degrees C for 2 min. The prepolymer on the microarray only contained 40% v/v raw/unpurified PCR products, 1.4% ammonium persulfate (APS), 6% acrylamide, and 20% glycerol and the balance H2O but no TEMED. The heat could induce the free radicals from APS to initiate polymerization of the 3-D gel and allow the incorporation of raw PCR products into the 3-D gel. The immobilized DNA on the gel microarray had the specificity of hybridization and the ability to distinguish base mismatch. It has been demonstrated that SNP genotyping of both the 194072 loci and the 252944 loci in the beta2 subunit gene of gamma-aminobutyric acid A receptor (GABRB2) gene was successfully performed by using the 3-D gel microarray. This method is efficient, simple, rapid, and easy to control in preparing a 3-D gel microarray, which would be widely used for various purposes in laboratory research and clinic application.