The antimicrobial susceptibility test (AST) is a technique used by modern laboratories to determine the response and resistance of certain pathogens through the growth of these microbial organisms in a suitable medium called "culture."
It is a method used by health professionals and clinical laboratory scientists to offer treatment for several infectious diseases that are mainly caused by microbes such as bacteria and viruses. This process is common now in vaccine manufacturing and which, in the long run, helps control infectious diseases in individuals and the wider population.
Antimicrobial testing is also important and necessary for the manufacture and formulation of antiseptic hand sanitizers. The main reason for this is to prove its effectiveness to untested colleagues and to maintain a certain standard of work.
Formulas must be properly evaluated to check whether other elements such as rehydrates or moisturizers are required without compromising antimicrobial properties. The two main test methods for hand sanitizer antimicrobial testing are:
Minimum Inhibition Concentration Test (MIC)
Standard in vitro time killing procedure
However, both methods have certain limitations. In the MIC method, the disinfectant formula has no direct effect on "killing" the microbial pathogens, and in the second method, in vitro or ex vivo testing, its effect on human skin is not possible.
Trials promise very little data on the ability of certain formulations to adequately reduce hand-transmitted infections. Clinical trials can be seen as the best approach to overcome this limitation. However, it is expensive and annoying. Despite these limitations, the latest tests fall into two or more main categories.
In most of the trials, participants' hands were deliberately contaminated with certain pathogens to be tested and then applied a hand sanitizing formula or hand test. The second category relates to preoperative exfoliation, and this procedure evaluates the formulation to test its ability to reduce pre-releasing pathogens in the hands of the subject.