Miniature PH Sensor Based on Electropolymerized Polyaniline

  • Karen S. Santiago Research Center for the Natural Sciences, University of Santo Tomas, Manila
  • Christina A. Binag Research Center for the Natural Sciences, University of Santo Tomas, Manila
Keywords: polyaniline, conducting polymer, BSA dopant, CV, SEM, XPS

Abstract

A miniature pH sensor was fabricated by electrochemical polymerization using 0.10 M aniline monomer, 30 mg bovine serum albumin (BSA) dopant, 0.10 M tris(hydroxymethyl)-aminomethane at pH 7, 30-minute polymerization time without stirring, platinum wire support and 9.34 mA cm^2 current density as optimum conditions. It showed a sub-Nemstian response of -42.06 mV/pH+ 0.5, a linearity of -0.9985 and favorable response time of ~3 min for three replicates from pH 3 to pH 10 at room temperature. The sensor exhibited low hysteresis with Δm = 5.83 mV/pH, low drift with an RSD = ~<4%, high reproducibility with an RSD = ~<3% and lifetime of > 1.5 months. Furthermore, extensive electrochemical and surface studies was carried out via Cyclic Yoltammetry (CV), Scanning Electron Microscopy (SEM) and X-ray Photoelectron Spectroscopy (XPS).
How to Cite
Santiago, K. S., & Binag, C. A. (1). Miniature PH Sensor Based on Electropolymerized Polyaniline. KIMIKA, 17(1), 19-25. https://doi.org/10.26534/kimika.v17i1.19-25
Section
Research Articles