An optically transparent biomaterial is produced by encapsulating a li
ght-transducing protein, phycoerythrin, in a sol-gel matrix. Absorptio
n and fluorescence measurements indicate that the protein not only ret
ains its native optical properties in the sol-gel matrix but also show
s an enhanced stability toward photodegradation. Two-photon induced fl
uorescence is observed from phycoerythrin in both solution and sol-gel
matrices. The potential application of this biomaterial in biosensors
, three-dimensional biomolecular imaging, and three-dimensional optica
l storage is discussed.