Hydrogels based on potyacrylamide are crosslinked networks of polymer swollen with water with good chemical and mechanical stability and resistance to microbial degradation. They have been extensively used as electrophoresis media and as support to immobilize enzymes or redox proteins [1, 2]. Electrodes modified with catalysts supported on electrochemically generated polymers offer the advantage of automatic deposition in a one-step operation with control of growth, adherence and thickness. Electropolymerization of vinyl polymers in solution has been extensively studied under different experimental conditions. However, most of the work has dealt with the production of polymer in solution [3, 5]. Anodic polymerization in solution is accomplished in the presence of acrylamide in organic solvents such as DMF [6, 7] or in aqueous solutions at iridium oxide [8, 9] and platinum [10]. Electroinitiation of soluble acrylic polymers is characterized by the presence of an induction time that has been related to the simultaneous oxidation of monomer, solvent and support electrolyte [11]. Under certain conditions formation of insoluble gel deposits at the anode has been observed [6]. The purpose of this work is to study the conditions under which a nonsoluble crosslinked copolymer of acrylamide and bisacrylamide deposits on platinum electrodes. The effect of electrode potential and concentrations of acrylamide, bisacrylamide and nitrate was investigated.