Electrospun antimicrobial poly(lactic acid) foams with nanocellulose for enhanced hydrophilicity and controlled drug release

Abstract

This study explores an advanced approach to enhancing the antimicrobial efficacy and hydrophilicity of poly(lactic acid) (PLA) scaffolds through the strategic incorporation of cellulose nanocrystals (CNC). The compatibility between these biodegradable polymers was investigated to optimize antimicrobial agent release while preserving structural integrity. PLA nanocomposites incorporating the antimicrobial agents curcumin (Cur) or polyhexamethylene biguanide (PHMB) were fabricated using three distinct electrospinning-based methodologies. The antibacterial properties were assessed via a disc diffusion test against five bacterial strains: Escherichia coli, Escherichia coli B+, Lactobacillus salivarius, Streptococcus sanguinis, and Streptococcus mutans. In addition, drug release experiments were conducted to determine the diffusion kinetics in a simulated blood serum medium, demonstrating sustained drug release for up to 98 hours. PHMB demonstrated potent antibacterial activity, while curcumin primarily exhibited bacteriostatic effects. The thermal stability of the nanocomposites exhibited an increase of up to 41 °C in the maximum degradation temperature. The mechanical properties were assessed to further examine the interactions between CNC and PLA and the possibility to reshape the materials for different delivery approaches. The findings underscore the crucial role of CNC in modulating the interaction between PLA and antimicrobial agents, making it a promising candidate for biomedical applications requiring controlled drug release. This study provides valuable insights into the structural, thermal, and antibacterial performance of CNC–PLA nanocomposites, establishing a strong foundation for the development of advanced biodegradable materials for drug delivery and antimicrobial applications.