The ability for selective ion recognition is a field of interest for a range of different chemical and biochemical disciplines. One such area that utilizes direct and selective recognition for analytical purposes is the potentiometric Ion-Selective Electrodes (ISEs). It is usually the case that the development of selective chemical sensors is dependent on the availability of the appropriate chemistry. The development of cation ISEs has been very successful with the use of multidentate crown ethers, analogs of natural antibiotics, and other synthetic ligands with basic coordinating groups. In this work, the new approach of utilizing organometallic complexing agents that possess one or more coordinating acidic metal centers, and which can selectively and reversibly bind to certain basic anions, is employed. The optimizing parameters for selectivity, stability and other electrochemical properties of certain compounds based on Sn(IV), and Mn(III) will be presented, as well as their application in novel ISEs.