Impact of HLB value and Emulsifier Mixtures on the Stability and Rheology of Carbamide Cream Formulations

Abstract

Abstract This study investigates the impact of Hydrophilic-Lipophilic Balance (HLB) values on the stability and rheological behavior of carbamide cream formulations. Using a mixture of non-ionic surfactants, Sorbitan oleate80/Polysorbate 80 and Sorbitan oleate 80 with Decaglycerol distearate, various cream formulations were prepared with differing ratios of emulsifier mixtures, resulting in HLB values ranging from 4.3 to 8.8. Rheological tests, including viscosity, frequency sweep test, thixotropic and multiple creep tests, were conducted across three different formulations: using only Sorbitan oleate 80, a mixture of Sorbitan oleate 80 and Decaglycerol distearate, and a mixture of Sorbitan oleate 80 and Polysorbate 80. Analysis of pH values, immediate stability, and water-to-oil ratio revealed significant impacts of emulsifier HLB values and mixtures on cream stability. Overall, our findings underscore the crucial role of HLB values and emulsifier mixtures in determining the stability of emulsions in cream formulations.