RAPID BACTERIA DETECTION BASED ON GELATIN LIQUEFACTION WITH A PIEZOELECTRIC VISCOSISENSOR

A simple, rapid, on-line method is proposed for monitoring the viscosi ty changes caused by Proteus sps. in gelatine-containing liquid medium . The different start times of gelatine liquefaction, which were in di rect proportionality with the bacteria concentration and frequency shi fts in certain time, can represent the gelatine liquefaction capacity of different strains. This principle is used to do qualitative analysi s of strains having or not having gelatine liquefaction within a short time (4-6 hr) and perform quantitative analysis simultaneously, since justifying gelatine liquefaction of bacteria from cultures by convent ional methods is very difficult and time-consuming (at least 24 hr or up to a week). The greatest advantage of the sensor is to obtain quali tative and quantitative information at the same time. The viscosisenso r also provides real-time measurement of antibiotic susceptibility. So me other factors, such as pH and temperature, are also discussed.