Friday, October 1, 2010
Bio meets nano: Quantum dots as light antennas for artificial photosynthetic systems: In organisms, the first step of photosynthesis is the absorption of light by an antenna, a complex of proteins and pigments that is brought into an electronically excited state by light energy. The energy packet can then be passed on to special chlorophyll cofactors in the reaction center of the photosynthetic apparatus. There the energy is finally used to produce cellular energy stores such as ATP. The passing-on of the energy packets occurs through a special radiation-free process called Förster resonance energy transfer (FRET), in which the electronic states of the sender and receiver of the energy packets must be brought into resonance.