Factors Influencing the Antimicrobial Activity of Chemical Agents
The following factors will affects the activity of a disinfectant or antiseptic and these should be borne in mind during use.
a. The Concentration and kind of a chemical agent used
The higher the concentration of the germicide the greater will be the rate of killing. This is particularly important with the phenolic group of compounds, whose activity falls off very rapidly with dilution.
b. Time of exposure to the agent
In general germicidal activity is increased with time and a sufficient exposure is imperative for efficient disinfection.
c. Temperature at which the agent is used
An increase of temperature will also raise the rate of killing.
d. Presence of Organic matter
Most germicides are reduced in activity by the presence of organic matter and particularly by the presence of proteins such as those in body fluids.
e. Number of organisms present
The larger the number of organisms, the greater will be the time required for disinfection.
f. The kinds of microorganisms present - Presence of spores
Spores are exceptionally resistant to the great majority of disinfection.