Biomass Conductivity Estimation of Escherichia Coli

ABSTRACT

The biomass of Escherichia coli is measured from dilutions 10⁻¹¹ to 10⁻¹. The effect of 0.05M Na₂HPO₄—C₃H₅0(COOH)₃ buffer (pH 6.6, 7.2, 7.8) on conductivity is experimentally obtained. The conductance is increasing with higher pH and temperature. A high correlation coefficient between the number of E. coli cells, measured by the conductivity and standard methods is defined (r=+0,911). The experimentally received data are comparative to these obtained by the standard microbiological methods. Other factors having influence on conductance are also discussed: cells electrical charge, cells and metabolites aggregation, concentration of different ions, etc. Conductivity appears a highly sensitive and express physical method that could be easily used for experimental needs of biomonitoring, clinical practice and biotechnology.