A new method based on gelation of tachypleus amebocyte lysate for detection of Escherichia coliform using a series piezoelectric quartz crystal sensor Original Research Article

A new method utilizing a series piezoelectric quartz crystal (SPQC) sensor was used to monitor the gelation of Tachypleus amebocyte lysate (TAL) and this reaction was applied to determine the Escherichia coliform (E. coli). The technique depended on the change of conductivity and permittivity during the course of gelation. This method was rapid and sensitive. Some factors affecting the determination were discussed. Results showed that the frequency shift was linearly related to the logarithm of E. coli concentration in the range of 2.1×104–2.1×108 cells/ml. The correlation coefficient is 0.993. This SPQC-TAL method was compared with the standard pour plate counts (PPCs). The proposed method for detection of E. coli is much faster and simpler than the traditional methods.