Nonleaching antimicrobial cotton fibers for hyaluronic acid adsorption

Quaternary ammonium containing compounds (QACs) such as cetylpyridinium chloride (CPC) is commonly employed in hyaluronic acid (HA) production process as an HA precipitating agent. 3-(Trimethoxysilyl)-propyldimethyloctadecyl ammonium chloride, a Si containing QAC (Si-QAC) generally used to modify the surface of cotton fibers for the preparation of nonleaching antibacterial textiles, has a chemical structure very similar to CPC. Choline, a natural QAC, can form a deep eutectic solvent with urea and be grafted onto cotton surface when incubating cotton in the deep eutectic solvent. Both of the QAC-modified cottons demonstrated antibacterial activity against Gram (−) Escherichia coli and Gram (+) Bacillus subtilis along with HA adsorption capacity. The HA adsorption isotherm could be well-fitted with Langmuir model with maximum adsorption capacities of 184 mg/g and 351 mg/g for Si-QAC and choline surface-functionalized cotton fibers, respectively. In the presence of high concentration of contaminants, HA could be directly recovered from a B. subtilis culture with a capacity of 15 mg/g by using Si-QAC modified antimicrobial cotton fiber.