Mechanisms of laser damage to Chlorella cells

A study was made of the interaction of laser radiation with Chlorella microalgae cells. The cell damage was found to be a function of the laser wavelength and power, and of the temperature of the cell suspension during irradiation. Possible damage mechanisms were considered, including local heating due to absorption of ruby laser radiation by intracell pigments when energy migration processes were saturated, heating-induced breaking of molecular bonds, and subsequent denaturation of biological membranes. These hypotheses were confirmed by spectrometric and pyrometric measurements.