Facile and single-step entrapment of chloramphenicol in ZIF-8 and evaluation of its performance in killing infectious bacteria with high loading content and controlled release of the drug

Abstract

Mutations in infectious bacteria and reduced drug efficacy have forced researchers to test new systems that combine carriers and drugs to improve performance. Here, CLN@ZIF-8 nanoparticles were synthesized by simple single-step entrapment of chloramphenicol (CLN) in zeolitic imidazolate framework-8 (ZIF-8). Chloramphenicol is a widely used antibiotic and ZIF-8 is a MOF (metal–organic framework) with proven good properties as a carrier. In this route, a high drug loading content (DLC) of 32.58 ± 2.65% and a drug loading efficiency (DLE) of 56.80 ± 6.68% were obtained. In a new and practical approach, drug release was evaluated under conditions similar to infectious environments containing higher concentrations of H₂O₂ and controlled release was achieved. Phosphate buffer played a decisive role in the destruction of the structure and release of the drug. The antibacterial activity was also measured by viable cell count assay and the results showed that CLN@ZIF-8 had a favorable efficacy in a short time. The structure of the compounds was also characterized using a variety of instrumental techniques.