Work

Simultaneous viscoelasticity and sprayability in antimicrobial acetic acid-alginate fluid gels

Year: 2024

Type: article

Abstract: Acetic acid is a promising alternative to antibiotics for topical applications, particularly burn wounds, however its site specificity and retention are impaired by poor material properties. In this study, acetic acid was investigated as both the gelling agent and antimicrobial active in alginate fluid gels. The formed microstructure was found to be directly dependent on acetic acid concentration, leading to highly tuneable material properties. At clinically relevant concentrations of 2.5–5 % acetic acid, the fluid gels were elastically dominated at rest, with viscosities up to 7 orders of magnitude greater than acetic acid alone. These material properties imparted long term surface retention and microparticle barrier function, not seen with either acetic acid or alginate solutions. Most notably, sprayability was enhanced simultaneously with the increased viscosity and elasticity due to the introduction of a discretised microstructure, leading to a remarkable tenfold increase in spray coverage. Formulation was found not to inhibit antimicrobial activity, despite the less acidic pH, with common burn wound pathogens Staphylococcus aureus and Pseudomonas aeruginosa being equally susceptible to the fluid gels as to acetic acid solutions. • Alginate forms a fluid gel when combined with clinically relevant concentrations of acetic acid under shear, • The formed microstructure means fluid gels are elastically dominated but can also be easily sprayed, • These properties allow ease of application and high targeted retention without compromising antimicrobial efficacy. • Acetic acid is a promising broad-spectrum antimicrobial used in burn units. • Formulation with alginate grants viscoelasticity through controllable microstructure. • Sprayability increases with viscosity and stiffness due to microstructuring. • Material properties improve retention at site and prevent further contamination. • Formulation does not impair antimicrobial performance of acetic acid.

Source: Biomaterials Advances

DOI: 10.1016/j.bioadv.2024.214051