Fixation and stability enhancement of beta-carotene by organo-modified mesoporous silica

beta-carotene is one of naturally occurring dyes, and has been used as a colorant because of its nontoxicity and biological functions. However, the color stability of the beta-carotene is not sufficient. The aim of this study is to enhance the stability of the beta-carotene by incorporation into the pore of mesoporous silica. Although the highly lipophilic beta-carotene does not generally meet rather hydrophilic inner pore space of mesoporous silica, the modification of the inner pore by alkyl chains enables the incorporation of the beta-carotene into the mesopore. The incorporated beta-carotene is successfully stabilized against visible light irradiation. Also improved is the durability of the dye in the composite sample against elution to the solvent. The effect of the complexation on the stability enhancement depends on the affinity of the lipophilic beta-carotene to the organo-modified inner pore space. (C) 2015 Elsevier Inc. All rights reserved.