Bacterial growth analyzer by impedance and turbidity

We describe a aicroprocessor-based coaputer-controlled instrument for the detection of aicroorganisas by simultaneous aonitoring of the iapedance and turbidity of an inoculated broth. Iapedance was dissected into a aedium resistive component and two electrode/electrolyte interface coaponents by using their frequency dependent properties. Turbidity was obtained by an LDR. The aediua resistive component and turbidity were almost coincident (maximum change: about 7 X). The interface components were siallar, but displaying larger changes than the two foraer (aaximum about 30 X). We concluded: (1) This iapedance/turbidity digital system is reliable for the recording of growth curves. (2) The interface components show changes that may offer criteria for faster quantification and identification of bacteria.