A novel amphiphilic thiosemicarbazone derivative for binding and selective sensing of human serum albumin.

The interaction of ligands and drug molecules with protein is of major interest in drug pharmacokinetics and pharmacodynamics. In this study, we synthesized a novel thiosemicarbazone-based amphiphilic molecule for selective binding and detection of human serum albumin (HSA) with significant increase in fluorescence intensity. The compound 5-(octyloxy) naphthalene substituted salicylaldehyde thiosemicarbazone was designed to interact with site I of HSA. The weak fluorescence of the probes in aqueous solution showed a dramatic increase in fluorescence intensity upon binding with HSA, while the responses to various other proteins and enzymes were negligible under similar experimental conditions. Changes in fluorescence intensity and formation of a new emission maximum of the compound in the presence of HSA as well as an increase in steady-state anisotropy values reflected well the nature of binding and location of the probe inside the protein environment.