Antimicrobial Efficacy Assessment and Rheological Investigation of Two Different Hand Sanitizers Compared with the Standard Reference WHO Formulation 1.

(1) Background: recently, the use of alcohol-based hand sanitizers (ABHSs) has become very frequent, and an evaluation of the stability and effectiveness of their formulations is a critical topic which should be carefully considered. (2) Methods: starting from the characterization of the hand sanitizers object of the study, our interest was focused on their rheological behavior in order to confirm their intrinsic features, but also the stability of each formulation in different conditions of shear and temperature; the second aspect concerns the antimicrobial assessment through a panel of in vitro and in vivo experimental trials. (3) Results: rheological investigation confirmed good stability for the two hand sanitizers in gel formula with respect to the reference in liquid formula; the antimicrobial activity evaluation showed good efficacy of each formulation both in vitro and in vivo. (4) Conclusions: altogether, our overview presents a valid quality control assessment to ensure the stability and efficacy of an alcohol-based hand sanitizer.