Disclosed herein is a method for the preparation of oligonucleotide microarrays obviating the drawbacks to an extent, such as time consuming complex chemical reactions, preparation of modified supports/oligomer modifying reagents, use of activating/condensing reagent, low signal to noise ratio, poor immobilization and hybridization efficiencies, etc. Further, the prepared arrays can be used to detect single or multiple nucleotide mismatches using hybridization assay.