Lignin-Based Infection-Resistant Biomaterials

Lignin-loaded poly(2-hydroxyethyl methacrylate)-co-poly(methacrylic acid) hydrogels were synthesised, while tetracycline hydrochloride (TET) was also loaded into the polymers for comparison. Synthesised hydrogels were validated with suitable drug releasing and loading abilities, desirable pH-sensitive characteristics as well as surface properties, and improved thermal stabilities. <br><br>After verifying the antimicrobial abilities of lignin, materials have been tested under both normal and infected urine conditions against urinary pathogens S. aureus (Gram-positive) and P. mirabilis (Gram-negative) to investigate their ability to reduce catheter associated urinary tract infections.

Lignin-loaded copolymers demonstrated similar antibacterial properties to TET-loaded copolymers by significantly decreasing relative bacterial adherence and reducing the planktonic cell density to below the LOD when incubated with S. aureus. Lignin-loaded hydrogels were more effective in inhibiting the growth of S. aureus compared to P. mirabilis in adherence tests, while lignin-loaded copolymers showed mixed results after incubation with P. mirabilis.