Abstract
The enzymic release of a model protein soil, crosslinked gelatin, has been observed in situ as an extended study of a series of those on the enzyme activity in detergency system. Namely, the frequency change of a quartz oscillator was traced for the release of the solid protein by Nagarse from the surface of the gold electrode. As observed in the former studies on dissolved protein, the synergetic effects were confirmed for the release by protease/nonionic surfactants, i.e., C12(EO)7 and C16(EO)7, and by protease/oxidizing agents, i.e., sodium perborate and sodium percarbonate.
The conclusions are as follows :
1) On addition of the enzyme in solution, the frequency of the quartz oscillator begins to decrease, and then turns to increase. These variations are interpreted as a result of the adsorption of the enzyme followed by the hydrolytic release of the gelatin from the electrode surface.
2) The addition of the nonionic surfactants in solution enhances the release rate as compared with the absent case. On the other hand, the addition of sodium dodecylbenzenesulfonate (DBS) or sodium dodecylsulfate (SDS) enhances the release rate at near cmc., but gradually reduces the rate at higher concentrations.
3) The synergetic effect of the oxidizing agents is oberved in the limited low concentration range.
