Entrapping sensitive material e.g. immobilization of biomolecules or immobilization of other light- pH- and/or temperature sensitive material is a demanding task in the art. That is immobilization of biomolecules within polymer matrices has gained considerable importance in various fields of biotechnical processes. For example photosynthetically active components which can absorb light and transfer energy may be immobilized (entrapped) within suitable immobilization compounds like polymer matrices for biotechnical processes. However photosynthetically active components are extremely unstable and need to be stabilised outside of the cell in order to use these highly effective components e.g. in third generation photoÃÂ¬voltaics and artificial photosynthesis respectively. The immobilized sensitive material includes active components like the mentioned photosynthetically active components but also optically and electrochemically active material. Beside encapsulation of whole cells cell compartments or cell organelles as well as biological macromolecules including proteins enzymes or other sensitive materials have been entrapped or encapsulated. In addition systems have been described wherein the sensitive materials have been encapsulated in biopolymers first and said encapsulated sensitive materials are coated with e.g. silica allowing to associate soft biocompatible components like alginate with a tough thermostable non-swelling component like silica. The present invention describes new transparent silica-based gel and Ã"glassÃ" with entrapped sensitive material which is in particular light- pH- and/or temperature- sensitive and furthermore a method of its preparation.