BAC ONE is based on a fragment of the antimicrobial peptide Ubiquicidin, arranged into a novel structure containing three peptide chains and three dyes per molecule. This compound inserts itself into the membrane of both Gram-positive and Gram-negative bacteria. When it binds, the Smartprobe is activated and fluoresces, making it a global identifier of all bacteria.
BAC TWO is based on the known antibiotic Polymyxin, and is labelled with a fluorescent compound (also known as a ‘fluorophore’), NBD. This compound inserts itself into the membrane of Gram-negative bacteria and the fluorophore is activated, enabling the detection and therefore a distinction between Gram-positive and Gram-negative bacteria to be made.
Both bacterial probes have been extensively screened in sheep lung ventilation models. Within this system, the efficiency and speed at which the bacteria are detected have been determined with real-time imaging using an optical fibre.
In order to be used in our clinical trials, BAC ONE and BAC TWO have been synthesised to Good Manufacturing Practice (GMP) levels in our own Active Pharmaceutical Ingredient (API) lab, and are now been tested in humans for the first time.