A long-term operating algal biosensor for the rapid detection of volatile toxic compounds

A method for the stable long-termimmobilization of microalgal cultures wasdeveloped. Immobilized Klebsormidiumcultures were used in a biosensor systemfor air monitoring. The measurement ofbiosensor response was performed usingseveral parameters obtained from the PAMchlorophyll fluorescence technique. To testbiosensor response on toxic compoundsmethanol and formaldehyde, classified asvolatile organic compounds (VOC), were usedin concentrations relevant to human health.Our results showed that quantitativedetection of methanol vapour by thebiosensor is possible within minutes atconcentrations from 75 to 350 ppm.Additionally, due to reversibility of thebiosensor response signal and long-termstability, the biosensor was operationalfor 30 days with repeated exposure periodsto methanol vapour. We conclude that thealgal biosensor, in principle, is suitableto detect volatile toxic compounds such asmethanol and formaldehyde.