Stability of nitrile and vinyl latex gloves under repeated disinfection cycles

As severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission by fomites is one of the main concerns of coronavirus disease 2019, the World Health Organization advised on the use of protective gloves for handling contaminated surfaces and fomites. The shortage in the supply of personal protective equipment (PPE) due to the surging demand in conjuncture with the disposal of an unprecedented quantity of contaminated PPE into the landfill led to an interest for alternative platforms for the management of PPE. In this study, we evaluated the potential of reusing gloves after repeated disinfection cycles using six readily available and common sterilization methods: UV, ethanol, heat, steam, bleach, and quaternary ammonium compounds (quats) for the inactivation of SARS-CoV-2. For this, two commercially available medical-grade gloves, i.e. nitrile and vinyl (polyvinyl chloride) gloves were tested. Both types of gloves showed deterioration in mechanical and thermal performance with the use of quats as sterilization treatment while no remarkable change in properties was observed up to 20 cycles of disinfection for the other sterilization methods. The exceptions were that the vinyl and nitrile gloves did not tolerate steam/dry heat and UV treatment over 10 cycles due to likely dehydrochlorination and thermal degradation, respectively. Subsequent rounds of sterilization caused no significant change in the glass transition temperature (T(g)) of either medical gloves; however, quats caused a slight reduction in T(g) due to its plasticizing effect. Overall, the physical sterilization treatments including steam, dry heat, and UV allowed the gloves to retain their thermomechanical performance up to ten cycles of sterilization.