Sartorius Lab Instruments GmbH & Co. KG Bactair™ Culture Media Plate

This system for sampling airborne microorganisms allows impaction onto culture media plates, where the plates function directly as collection heads. This means that the collection properties are integrated right into the culture media plates. Metal sieve plates or metal collection heads with slots, which have to be sterilised for routine samplings on a regular basis, are eliminated. Now, non-sterile sieves or slots have become a thing of the past. The geometry of the culture medium plate and the 400 holes in the sieve plate yield exceptional sampling efficiency, which is generally higher than that of other impaction samplers. This new method uses the AirPort MD8 air sampler to pump the air stream. BACTairs™ are ready-to-connect to the AirPort MD8. The Tryptic Soy Agar (TSA) medium is used for the recovery of a broad range of heterotrophic microorganisms such as common aerobic and facultative anaerobic bacteria. Optimized Geometry The number of impaction-holes and their optimal position in relation to the sampling area are the key to reliable results. Recovery Comparison Study BACTair™ shows the highest recovery of bacteria due to optimized geometry and complete disposable design. Aerosols of three different bacteria suspensions are released into a sampling channel under defined conditions. At the end of the channel the aerosols are sampled using four different air monitoring methods. As a reference method two parallel impinger systems were used (100 % recovery). Correction Factors BACTair™ provides 400 air impaction holes. A correction factor is only relevant with very high CFU counts. The recovery of colony-forming units depends on the number of holes in the sieve plate onto which the air is impacted. The lower the number of holes, the higher is the risk that more than one microorganism will pass into one single hole (colony overlapping). Evaporation Effects Because of its optimal design BACTair™ shows the lowest desiccation effects and enables viable microorganisms to grow under optimal conditions. During the sampling period, agar media may dry out, thus inhibiting the growth of the collected microorganisms. The weight of several BACTair™ was measured prior to and after sampling and compared to other impaction agar plates or strips.