Use of fluorescence to monitor the incorporation of horseradish peroxidase into a sol-gel derived medium

The solvatochromic dye nile red has been employed to monitor the incorporation of an enzyme (horseradish peroxidase) into a sol-gel derived medium. The fluorescence spectrum of the dye, when incorporated into the enzyme, was analysed as the sum of Gaussian component spectra and relative changes between these component spectra were monitored upon encapsulation of the dye-enzyme system within the host matrix. Activity of the confined enzyme was verified and the effect of temperature was also investigated, through the examination of nile red fluorescence in the sol-gel derived matrix, where a stabilising effect was noted.