Effects of plasmonic film filters on microalgal growth and biomass composition

Polymer films consisting of spherical silver nanoparticles were fabricated and used as plasmonic filters that selectively enhance blue light absorption in microalgal cultures. For the microalgal species Chlamydomonas reinhardtii, after ten days of cultivation the use of plasmonic filters led to an increase in the microalgal dry biomass by more than 25% and an increase in chlorophyll and carotenoid pigments by more than 35%, compared to the control cultures without using these films. Further, light enhancement by plasmon resonance did not affect lipid and carbohydrate accumulation within individual algal cells. However, higher cell densities obtained with plasmonic filters resulted in enhanced overall carbohydrate and lipid production.