Thamarai Selvi, J2017-11-082017-11-0820170970-020 Xhttps://ir.avinuty.ac.in/handle/avu/3610A new, efficient Calcium ion selective electrode has been prepared using Surface modified Zeolite based ionophore.The prepared ionophore is characterized by UV,FT-IR,XRD..The sensor exhibits a near Nernstian response for Ca(ll) ion over a concentration range of 1.0 X 10’* M tol ,0 M . The proposed sensors revealed relatively good selectivity and high sensitivity tor Ca(ll) over a monovalent cations. It can be used with in the pH range of 5.57 to 6.24 . The effect of medium and the selectivity coefficient values was evaluated using fixed interference method found to give a better response.. It was also successfully used in the analysis of concentration of Calcium ion in various real samples.