Development of Integrated Planar Chloride Ion-Selective Electrode and Ag/AgCl Reference Electrode based on Chitosan/Cellulose Acetate Membrane for Blood Serum Analysis

The purpose of this study is to measuring the chloride ion concentration in blood serum using a pair of chloride ion-sensor and reference electrode at integrating single strip (ISS). The chloride ion-sensor is offered through the chlorination process of the Ag surface on the strip to form an Ag/AgCl layers are sensitive over of chloride ion. The reference electrodes have been fabricated using three membrane layers with different roles and compositions. The first layer is a mixture of Chitosan/Cellulose Acetate (CA) membrane doped with 3 M KCl salt, where the first layer is placed above the surface of the Ag/AgCl electrode that has been previously provided. The first layer acts as an inner layer. While the second layer is a mixture of Chitosan/CA membrane doped with 0.1 M KNO3 salt which acts as an outer layer. While the third layer is a CA membrane that acts as a protective layer. Chitosan/CA membrane mixture uses a ratio of 20:80. The ISS showed a good performance by generating range measurement 1 M–10-3 M and had selectivity towards H2PO4-=-3.40 to -3.64, HPO42-=-3.67 to -3.83, NO3-=-1.42 to -1.65, HCO3-=-2.29 to -2.35 and SO42-=-3.84 until -4.25. The measurement of chloride ion on blood serum gave results equivalent to the ISE commercial and the ion analyzer equipment