Continuous technology miniaturization using nanoscale materials allows the design of DNA sensing platforms with not only far larger surface areas but alsomore effective characteristics. We herein synthesized benzoic acid-functionalized graphene oxide (GOB), characterized by FT-IR, XPS, Raman Spectroscopy, TGA, SEM, TEM techniques and then it was utilized as a supporting material. Due to the benzoic acid groups available on the surface of GOB, fsDNA was directly immobilized onto the disposable pencil graphite electrode (PGE). The limit of detection (LOD) for fish sperm DNA (fsDNA) concentration was estimated to be 1.11 mu g/mL by using differential pulse voltammetry (DPV) technique. It can be assumed that this simple modification protocol offers an alternative for the quick and robust monitoring of sequence-specific nucleic acids avoiding the need of complex or expensive requirements, and it can pave the way for new opportunities to design more novel DNA sensing strategies and applications on disposable platforms. (c) 2017 The Electrochemical Society. All rights reserved.