Encapsulation of methyl orange pH-indicator into a sol-gel matrix
The acid catalyzed sol-gel reaction was used to encapsulate methyl orange pH-indicator into transparent monolithic silica matrices.
Tetraethylorthosilicate was used for the entrapment of the methyl orange indicator. The immobilized methyl orange shows similar behavior as
its solution counterpart. It retains its structure during the sol-gel reactions in terms of response to pH. The surface morphology indicates that
the methyl orange molecules are weakly interacted within the host silica network. This study shows that the methyl orange pH-indicator can
be doped into sol-gel silica matrix and used for sensing pH as a solid indicator.
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