Self-Gelling Liquid Composition for Topical Application of Medications

Abstract

The present work was carried out to modify a self-gelling liquid composition for fluoride application to teeth so it would gel with reduced fluoride content. Past work had shown that quaternary ammonium compounds with carbon chain lengths in the C₁₂ to C₁₆ range or surface modifiers such as hydroxylamine-HCl in conjunction with surfactants facilitated gelation in systems of tetraethoxysilane and aqueous sodium fluoride solutions containing 1,900 ppm or more fluoride. A search was conducted among amines, imines and heterocyclic compounds for agents that would facilitate gelation in systems with lower fluoride concentrations. The findings were that imidazole-HCl in conjunction with a surfactant could effect gelation within minutes in systems with as little as 100 ppm fluoride and, further, that gelation of such systems was not affected by the presence of a series of disinfectants, antibiotics or hormones. Thus, it appears that the self-gelling system may be used as a vehicle for medicaments other than fluoride.