Preparation and characterization of nanoemulsion based β-carotene hydrogels

The aim of this study was to develop β-carotene hydrogels using nanoemulsions, with increased β-carotene aqueous solubility, bioavailability and improved physical and chemical stabilities. The nanoemulsion of β-carotene was prepared using a solvent-displacement technique and converted into hydrogels using sodium alginate as stabilizer and calcium chloride as cross-linker. The effects of formulation parameters, mainly, the effects sodium alginate and calcium chloride concentrations on the physicochemical properties of hydrogels were evaluated using a surface response methodology. The second order polynomial equations, subsequently, were suggested to predict the changes of studied physicochemical characteristics of hydrogels, with relatively high regression of coefficients values. Based on numerical multiple optimization, it was concluded that using 4.1 g/l sodium alginate and 5.7 g/l calcium chloride, resulted in a hydrogel with the most desired physicochemical characteristics. No significant differences between the measured and predicted data, reconfirmed the accuracy of the models.