Piezoelectric cell growth sensor.

We have developed a reusable piezoelectric sensor that enables rapid characterization of cell viability and response to cell-affecting agents. This is accomplished via a novel polymer transduction principle that involves reaction of a pH-sensitive amphoteric polymer with metabolically generated acid. Subsequent adhesion of the protonated polymer to the transducer surface causes a decrease in the sensor resonant frequency corresponding to the cell metabolic rate. This disclosure provides the first example of a piezoelectric sensor capable of detecting metabolic responses of viable cells. The sensor provides real-time measurement of cell metabolism and division rates, and antibiotic sensitivity. This technology provides the basis for an advanced piezoelectric sensor that does not require immobilized biological receptors and can be miniaturized without compromising signal-to-noise factors.