Biomimetic recyclable microgels for on-demand generation of hydrogen peroxide and antipathogenic application

Abstract

Microgels that can generate antipathogenic levels of hydrogen peroxide (H2O2) through simple rehydration in solutions with physiological pH are described herein. H2O2 is a widely used disinfectant but the oxidant is hazardous to store and transport. Catechol, an adhesive moiety found in mussel adhesive proteins, was incorporated into microgels, which generated 1–5 mM of H2O2 for up to four days as catechol autoxidized. The sustained release of low concentrations of H2O2 was antimicrobial against both gram-positive (Staphylococcus epidermidis) and gram-negative (Escherichia coli) bacteria and antiviral against both non-enveloped porcine parvovirus (PPV) and enveloped bovine viral diarrhea virus (BVDV). The amount of released H2O2 is several orders of magnitude lower than H2O2 concentration previously reported for antipathogenic activity. Most notably, these microgels reduced the invectively of the more biocide resistant non-envelope virus by 3 log reduction value (99.9% reduction in infectivity). By controlling the oxidation state of catechol, microgels can be repeatedly activated and deactivated for H2O2 generation. These microgels do not contain a reservoir for storing the reactive H2O2 and can potentially function as a lightweight and portable dried powder source for the disinfectant for a wide range of applications.

Thermostabilization of viruses via complex coacervation

“…To determine the concentration of the infectious virus, an MTT assay was used. Briefly, either 8 × 10 4 cells per mL PK-13 cells in completed MEM media (to titrate PPV) 46 or 2.5 × 10 5 cells per mL BT-1 cells in completed DMEM media (to titrate BVDV) 47 were seeded in a clear, flat-bottom, 96-well plate in a volume of 100 µL per well. After one day of incubation, 25 µL per well of virus sample was added to the corresponding host cells in quadruplicate and serially diluted across the plate.…”

Antibacterial Activity against Methicillin-Resistant Staphylococcus aureus of Colloidal Polydopamine Prepared by Carbon Dot Stimulated Polymerization of Dopamine

“…This work unraveled a considerable antibacterial effect against S. aureus (Gram-positive), and a similar mechanism could be suggested for cell death. The binding of a bacterial membrane with PDA plays an important role in the death of this pathogen, which has been known to release different cytolytic toxins [47,48] to damage the host tissue. In addition, S. aureus releases~20 enterotoxins and enterotoxin-like toxins to cause emesis and diarrhea.…”

Development and Characterization of an Antimicrobial Polydopamine Coating for Conservation of Humpback Whales

“…Coupons were coated and the H 2 O 2 generation was measured using a previously established protocol (Meng et al, 2019). Briefly, a ferrous oxidation-xylenol orange (FOX) colorimetric assay (Sigma Aldrich, St. Louis MO) was used to measure the H 2 O 2 generation when the coupons were incubated at 21 and 35°C in a PBS solution at various time points.…”

“…However, concerns regarding potential antimicrobial resistance (AMR) have made developing non-antibiotic based antimicrobial approaches of growing clinical importance. For this reason, the development and use of reactive oxygen species (ROS) based antimicrobial systems has become an area of interest (Vatansever et al, 2013; Meng et al, 2019). These species have been shown to have varying capacity to affect bacteria and mammalian cell type growth and survival on a dose-dependent basis.…”