We report on the synthesis of 2-dimensional transparent graphene flakes (GF; 2.2 mu m x 50 mu m), onto indium-tin-oxide (ITO) coated glass plates, by electrochemical exfoliation of graphite rods using in situ intercalation of potassium ions. Raman spectroscopy, Fourier transform infra-red (FT-IR) spectroscopy, scanning electron microscopy and transmission electron microscopy, are used to probe the formation of graphene structures, revealing the generation of GF. Synthesized GF are employed as DNA immobilization platform for genosensor design for Mycobacterium tuberculosis detection. This GF based biosensing electrode exhibits high sensitivity, fast response and wide detection range etc. These findings are important for cost-effective strategy for the production of GF for application to advanced biosensors, and to understand graphene-based biosensing mechanism specifically for nucleic acid detection