Synthesis, Characterization, and Investigation of the Antimicrobial Activity of Cetylpyridinium Tetrachlorozincate

Cetylpyridinium tetrachlorozincate (referred to herein as (CP) 2 ZnCl 4 ) was synthesized and its solid-state structure was elucidated via single-crystal X-ray diffraction (SC-XRD), revealing a stoichiometry of C 42 H 76 Cl 4 N 2 Zn with two cetylpyridinium (CP) cations per [ZnCl 4 ] 2- tetrahedra. Crystal structures at 100 and 298 K exhibited a zig-zag pattern with alternating alkyl chains and zinc units. The material showed potential for application as a broad-spectrum antimicrobial agent, to reduce volatile sulfur compounds (VSCs) generated by bacteria, and in the fabrication of advanced functional materials. Minimum inhibitory concentration (MIC) of (CP) 2 ZnCl 4 was 60, 6, and 6 μg mL -1 for Salmonella enterica , Staphylococcus aureus , and Streptococcus mutans , respectively. The MIC values of (CP) 2 ZnCl 4 were comparable to that of pure cetylpyridinium chloride (CPC), despite the fact that approximately 16% of the bactericidal CPC is replaced with bacteriostatic ZnCl 2 in the structure. A modified layer-by-layer deposition technique was implemented to synthesize mesoporous silica ( i.e ., SBA-15) loaded with approximately 9.0 wt % CPC and 8.9 wt % Zn.