Polyaniline-coated Calotropis procera L. hollow tubular fibers with remarkable antibacterial activity

The development of environmentally friendly prototypes for use as antibacterial agents and as alternatives to antibiotics is a necessary step toward the control of infections. With this in mind, the production of hybrid composites based on natural and synthetic materials has been successfully explored. Herein, the chemical polymerization of polyaniline on natural fibers of Calotropis procera was used to explore the combined available surface area of fibers with the intrinsic properties of the conductive layer of PANI. What resulted was a coating of conducting polymer on natural fibers with strong antibacterial activity against Staphylococcus aureus and Escherichia coli. The characteristic time for the complete elimination of colonies (kill time) observed in assays was in the region of 3–4 h of treatment, with an inhibition halo of 20 mm (against E. coli) and 24 mm (against S. aureus). In addition to the antibacterial activity against S. aureus and E. coli, the modified fibers exhibited antibiofilm activity against S. aureus, which was evidenced in the reduction in the degree of bacterial adhesion to the surface applied in treatment (with a 39.96% biofilm inhibition). The proposed method represents a simple, low-cost, and one-step method for the modification of natural fibers with relevant applications in antibacterial agents.