Mechanisms and Control Measures of Mature Biofilm Resistance to Antimicrobial Agents in the Clinical Context

Biofilms are the aggregation of micro-organisms, which are composed of extracellular polymeric substance (EPS) and many other biochemical components. Though they might be beneficial to some wastewater and soil treatment processes, they may expose chronic infection and risk to personal hygiene in the industrial as well as the clinical context. Despite having a well-established disinfection and hygiene monitoring program for the prevention of formation and growth, biofilm persistently remains in the medical settings because of its antibiotic resistance to antimicrobial agents and even the immune system. In this paper, the contributing factors of antibiotic resistance and the corresponding mechanisms, including heterogeneity inside biofilms, the roles of the EPS matrix, cell density, and quorum sensing, and cell mutability, are reviewed. Moreover, current clinical practice and strategic applications are also suggested to address the biofilm resistance issues.