Amikacin sulfate loaded natural rubber latex films: Characterization and antibacterial performances

Natural rubber latex (NRL), obtained from Hevea brasiliensis, comprises particles of long-chain poly(cis-1,4isoprene) molecules. It is a naturally occurring, biocompatible polymer that acts as a stable matrix for precise drug release. Amikacin sulfate (AS) is a broad-spectrum semi-synthetic aminoglycoside antibiotic frequently used to treat Gram-negative bacterial infections. This study focuses on developing amikacin sulfate-loaded NRL (ASNRL) films, characterizing their physicochemical properties, evaluating their antibacterial and antibiofilm activities, and assessing their cytocompatibility. The AS-NRL films were prepared using a casting method. Their physicochemical properties were characterized by fourier transform infrared spectroscopy (FTIR), mechanical testing, scanning electron microscopy (SEM), and static contact angle assessments. The antibacterial and antibiofilm efficacy of the films was evaluated against strong biofilm-forming, multi-drug resistant (MDR) strains of Klebsiella spp. and Pseudomonas spp., isolated from indwelling urinary catheters (IUCs). This investigation confirmed that amikacin sulfate was effectively incorporated into the natural rubber latex films. Surface topography analysis by SEM also confirmed the presence of amikacin sulfate on the film surface. All films possessed sufficient elasticity for catheterization. The antibacterial and antibiofilm assays confirmed the ability of the AS-NRL films to control bacterial growth and minimize biofilm formation, supported by live/dead staining assays and SEM imaging. NRLA4 films retained antibacterial activity after leaching in artificial urine for 21 days against all tested bacterial strains. The AS-NRL films showed cytocompatibility in vitro. This work demonstrates that AS-NRL films are promising biomaterials for developing urinary catheters, potentially reducing CAUTI and the undesirable side effects of high-dose antibiotics.