A new light-harvesting antenna complex could pave the way for making low-environmental-impact, biologically based solar cells. Challa V. Kumar and his team at the University of Connecticut made the biodegradable antenna from a self-assembling mixture of DNA, modified bovine serum albumin, and four fluorescent dyes. One dye binds to the minor groove of the DNA double helix; the other three bind to specific sites on the albumin. The dye-loaded protein in turn binds to the negatively charged DNA because the researchers chemically modified the albumin to be positively charged. The arrangement allows efficient energy transfer between the dyes. With the current set of dyes, the antenna absorbs blue light and then emits mostly red. The overall efficiency of the antenna in converting blue to red photons is only 23%. But that efficiency is still remarkable because, based on the efficiency of the final dye, the system’s theoretical upper limit is 39%, Kumar said. The antenna also functions efficiently after exposure to 80 °C for more than 169 days, which mimics the harsh conditions under which solar cells operate.