Degree of Complexation of Anticoagulant Rodenticides with Human Serum Albumin: Effect of Saccharose and Sodium

A theoretical treatment has been developed to describe association between rodenticides and human serum albumin (HSA). The degree of complexation n_c (the amount (%) of complexed guest) and the association constant (K) for rodenticide–HSA binding were determined. Enthalpy–entropy compensation was also investigated in relation to this mathematical model to confirm rodenticide binding behavior with HSA. The role of the sodium cation and saccharose in this association were also analyzed. As expected for a salting-out agent, addition of Na⁺ cation to the mobile phase led to enhancement of n_c and K values by increasing the hydrophobic effect. When saccharose was increased above a critical x_c value equal to 4 mM, a decrease of the association constant and the degree of complexation was observed, owing to reduction of the radius of curvature of the HSA cavity.