Although described almost a century ago, interest in
ionic liquids has flourished in the last two decades, with significant advances in the understanding of their chemical, physical and
biological property sets driving their widespread application across multiple and diverse research areas. Significant progress has been made through the contributions of numerous research groups detailing novel libraries of
ionic liquids, often 'task-specific' designer
solvents for application in areas as diverse as separation technology, catalysis and bioremediation. Basic antimicrobial screening has often been included as a surrogate indication of the environmental impact of these compounds widely regarded as 'green'
solvents. Obviating the
biological properties, specifically toxicity, of these compounds has obstructed their potential application as sophisticated designer
biocides. A recent tangent in
ionic liquids research now aims to harness tuneable
biological properties of these compounds in the design of novel potent antimicrobials, recognising their unparalleled flexibility for chemical diversity in a severely depleted antimicrobial arsenal. This review concentrates primarily on the antimicrobial potential of
ionic liquids and aims to consolidate contemporary microbiological background information, assessment protocols and future considerations necessary to advance the field in light of the urgent need for antimicrobial innovation.