Silver(I) N‑Heterocyclic Carbene Complexes Derived from Clotrimazole: Antiproliferative Activity and Interaction with an Artificial Membrane-Based Biosensor

With the aim of combining the potential anticancer properties of both clotrimazole, an imidazole based antifungal agent, and silver(I) N-heterocyclic carbenes, 13 novel silver(I) N-heterocyclic carbene complexes derived from clotrimazole were synthesized. The complexes were fully characterized, and the partition coefficient of each was determined to provide a measure of hydrophobicity. The antiproliferative properties of the complexes against cancerous and noncancerous cell lines found optimum cytotoxicity when the complex displays an "intermediate lipophilicity", which describes a complex that possesses both water-soluble groups and lipophilic aromatic groups. The silver complexes were screened on a synthetic biomembrane-like device using a chip-based phospholipid-coated Pt/Hg electrode embedded in a flow cell system. The results are recorded as rapid cyclic voltammograms (RCVs), which give insight into the interactions of the complexes with a cell membrane. Interestingly the principle of "intermediate lipophilicity" also applies to the monolayer interaction to which the silver atom significantly implements an irreversibility.