Measurement of Spectroscopic Properties of Sol-Gel Coated Fiberoptic Appliances

We examined the spectroscopic properties of sol-gel coatings doped with photosensitive dyes on optical fibers cores. The coatings were prepared from silicate precursor TEOS (tetraethylorthosilicate) mixed with ethyl alcohol in acid catalyzed hydrolysis produced with ratio R = 20, whereas R denotes the number of solvent moles (here ethanol) to the number of TEOS moles. It was demonstrated that PDT photosensitive agents (Photolon and Protoporphyrine PPIX) immobilized in sol-gel show the clear response to changes in environment. This may be exploited for construction of fiberoptics sensors or applicators for interstitial photodynamic therapy (PDT).