Abstract：A method to determine the content of nucleic bases Cytosine (Cyt) and Adenine (Ade) by electrode potential titration in non-aqueous soolvent is established.The factors affecting the experiments, such as non-aqueous solvent, titrant, the concentration of titrant, and end point of the titration are determined.The optimal experiment conditions determined are glacial acetic acid (HAc) as the non-aqueous solvent,perchloric acid as titrant (HClO4),titrant concentration 0.05 mol/L,and equivalence point of the electrode potential titration curve as endpoint.Through 15 times measurements and uncertainty evaluation, the purity of Ade is 99.40% ±0.38% (k=2), Cyt 99.58%±0.42% (k=2).
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2013, Vol. 34 
