A rapid method for determining Mycobacterium tuberculosis based on a bulk acoustic wave impedance biosensor.

The bulk acoustic wave impedance biosensor was set up and used to monitor the growth of Mycobacterium tuberculosis (M.TB). This sensor is rapid, simple, sensitive (lower limit is 2 x 10(3) cells ml(-1)) and cheap (easy to generalize). The typical response curve was different from other bacteria's, such as Escherichia coli, Staphylococcus aureus, Proteus mirabilis. The frequency detection time was used to quantitatively determine M.TB. It was proportional to logarithm of the initial concentration of M.TB in the range of 2 x 10(3)-3 x 10(7) cells ml(-1). The set up sensor was applied to the direct diagnosis of M.TB samples. The interference of other bacteria was eliminated by pretreatment. Our results confirmed that the use of the set up biosensor was reliable, sensitive. It gives out the potential use for determining M.TB.