A combination biocide (Glutaraldehyde or OPA), quaternary phosphonium biocide, alcohol, and functional excipients for surface-sterilization of medical instruments and other objects. The quaternary phosphonium biocide is preferably TTPC, and the alcohol isopropyl alcohol. The OPA is the dialdehyde C6H4(CHO)2, which produces an inherent bacteriostatic effect, lowering surface tension, and aiding in the spread of the TTPC on the instrument surface where it is readily absorbed by the negative surfaces of proteins and bacteria. It thus serves as a binding agent between the TTPC and the application surface. The foregoing constituents are combined in preferred concentrations within acceptable ranges to provide a synergistic formulation that combines biocidal molecules in a biological chemical system that actively transports itself into the cells, through biofilm and cell wall/membranes, thereby overcoming penetration restraints to improve kill and kill time, without the need for activation or any time or temperature control.
