Oxygen activatable formulations for disinfection or sterilization

Methods and compositions are disclosed for producing air-activated, i.e., oxygen (O2) activated, disinfectant-sterilent solutions. Solutions containing a haloperoxidase (i.e., a halide:hydrogen peroxide (H2O2) oxidoreductase, such as myeloperoxidase, eosinophil peroxidase or lactoperoxidase) plus a halide or combination of halides (i.e., chloride, bromide and/or iodide), an oxidase (i.e., a substrate:O2 oxidoreductase) capable of generating H2O2, and a substrate specific for that oxidase, are separately prepared under aerobic conditions, but all of the component solutions are made anaerobic prior to final combination and mixing. The anaerobic formulations are dispensed into containers capable of maintaining the anaerobic condition (e.g., pressurized canisters). Dispensing the solution at the time of use exposes the formulation to air (i.e., O2) which activates its disinfectant-sterilent properties. O2 is the rate limiting component for oxidase generation of H2O2. Under aerobic conditions the oxidase catalyzes the oxidation of its substrate and the reduction of O2 to generate H2O2. In turn, H2O2 serves as substrate for haloperoxidase which catalyzes the oxidation of halide to hypohalous acid. Hypohalous acid reacts with an additional H2O2 to generate singlet molecular oxygen (1O2). Hypohalous acid (e.g., hypochlorous acid) and especially 1O2 are potent microbicidal agents. Both haloperoxidase generation of hypohalous acid and its reactive consumption to yield 1O2 are dependent on the availability of H2O2. A high rate of H2O2 generation does not result in the accumulation of hypohalous acid, but instead results in a high rate of 1O2 production. The microbicidal capacity and toxicity of 1O2 are limited by the half-life of this metastable electronically excited reactant, and as such, disinfectant-sterilent activity is temporally defined by and confined to the dynamics of oxidant generation. The disinfectant-sterilent activity of formulation requires air exposure and is dependent on the presence of the halide-haloperoxidase combination employed, the activity of the oxidase present, the availability of oxidase-specific substrate and the availability of O2.