Modeling of Radiometal Complexation Formation with Bifunctional Coupling Agents Using Ligand-Metal Interaction Profile

This study aims to establish generalized models for predicting the complex formation (KML) of Ga(III),Cu(II) and In(III) radiometal ions with bifunctional coupling agents of diverse structures. The models were developed based on three different blocks of descriptors e.g. ligand descriptors, metal ions properties and cross-term variables for the analysis of ligand-metal interaction profile. Multiple linear regression (MLR) and support vector regression (SVR) have been utilized to construct the models. The final models showed the best statistical results with squared correlation coefficients of 0.84 and the standard error of estimation (SEE) and standard error of prediction (SEP) values of 2.8 and 3.2 logKML units respectively. The final models were checked for chance correlation, reliability and robustness by permutation testing of y scrambling and cross-validation procedures. The results elucidate the contribution of hydrogen bonding and electrostatic interactions, shape and size of organic ligand and the coordination and electron configuration of metal ions to the complex formation.