Membrane-sealed Bioreactor for On-site Autonomous Detection of Fungi Spore Contamination in Archives

Abstract We present a miniaturized culture medium based bioreactor for monitoring airborne fungal spores. The bioreactor is sealed with an electrically actuated sacrificial membrane, which is opened at the desired time of measurement. An air sampling system is integrated allowing on-site autonomous operation. The monitoring system consists of a bioreactor provided with sensors, a sacrificial silicon nitride membrane, an air pump for directing the spores into the bioreactor and readout electronics with a data logger. Sealing the bioreactor with a burstable membrane prevents the contamination of the medium of the unused sensors. Once a membrane is actuated, it bursts open due to thermal stress and the spores get in contact with the medium. The growth of fungi in the sensor is quantified with an integrated approach of impedance and colorimetric methods.