Simultaneous determination of guanine, adenine, thymine and cytosine with a simple electrochemical method

A simple method for simultaneous detection of guanine, adenine, thymine and cytosine was set up by using a bare glassy carbon electrode in acetate buffer solution of pH 4.5. The peak current responses of these four DNA bases in this supporting electrolyte were significantly increased comparing with those in phosphate buffer solution and Tris-HCl, moreover, the peak current values were linearly dependent on the concentration of four DNA bases, respectively. Individual and simultaneous determinations of four bases were performed by controlling certain experimental conditions, and broad linear ranges and low detection limits (S/N = 3) were obtained. The assay processes do not need any separation or pretreatment steps. In addition, this method showed good selectivity, reproducibility, and stability and can be used for determination of the four bases content in real DNA sample.