Sodium dodecyl sulfate (SDS) is an anionic surfactant that has unique molecular structure. Therefore, it has become very popular for application in various fields of electrochemistry. SDS adsorption hydrophobic on the surface of CPE causes high density of negative charges covered on electrode surface. Some biomolecules in certain forms might combine with SDS through electrostatic interactions. This interaction assisted the electron transfer between the solution and the electrode. Hence, sensitivity enhanced the presence of anionic surfactant SDS.