Determination of microorganisms with a quartz crystal microbalance sensor

A technique using a quartz crystal microbalance sensor coated with a thin culture medium film was developed and successfully applied to determine the number of Staphylococcus epidermidis (S. epidermidis) in the range of 1 × 102 −4.1 × 107 cells ml−1, based on a good linear relationship between the turning point time and the number of S. epidermidis. The technique is fast and accurate for detection of microorganisms due to the thin culture film and the sharp turning point of the response. The experimental conditions were discussed in detail.