This laser kinetics features of the electron decay of TiO2 in the presence of the Escherichia coli (E. coli) phosphatidyl-ethanolcholine (PE) and lipo-polysaccharides (LPS) cell wall components were are reported in this study. The interaction of the biomolecules with the photogenerated charge carriers was determined and the reaction rates were measured. The effect of the variation of ionic strength of the colloidal TiO2 on the electron decay was determined in the presence of PE and E. coli. The ionic strength seems to affect the equilibrium absorption of the biomolecules on TiO2. The e− decay was measured for TiO2 samples having different sizes, charge and isoelectric points (IEP) by laser spectroscopy for different types of TiO2. TiO2 Degussa P-25 mediated the E. coli abatement most effectively compares to other TiO2 samples. The structural features of different TiO2 samples were related to the degradation of E. coli and also related to the fast kinetics results.