The Impact of pH on heat killing of <i>Clostridium difficile</i> spores exposed to chlorhexidine gluconate (CHG).

<p>The mean log₁₀colony-forming unit (CFU) reductions of <i>C</i>. <i>difficile</i> spores achieved after 1 or 3 hours of incubation in pH altered aqueous and alcoholic CHG solutions (0.04% w/v). Elevating the pH to ≥9.5 significantly enhanced the killing of spores in either aqueous or alcoholic CHG solutions (<i>P</i> <0.001 for each comparison to pH 4.0). In aqueous or alcoholic CHG solutions, increasing the pH to ≥9.5 enhanced heat killing of spores by ≥1log₁₀CFU after 3 hours of incubation. The means of the data from experiments conducted in triplicate are presented. Error bars indicate standard error.