Environmentally degradable curcumin/ zinc oxide nanoparticles-incorporated polycaprolactone films for use as top-sheets in feminine sanitary hygiene napkins

Fabrication of environmentally degradable topsheets of feminine sanitary napkins is a challenging area in biomedical studies. Commercial topsheets comprise polyethylene and polypropylene and are a huge source of non-degradable municipal waste. This study addresses the development of synthetic scaffolds of nanofibrous polycaprolactone (PCL) polymer, a polyester with enzymatic and hydrolytic degradable ester (-COO-) linkage. Curcumin, an organic phytochemical with antimicrobial properties and ZnO, an inorganic nanofiller with significant ROS (reactive oxygenated species) generating-ability are included in the polymer matrix for enhanced antibacterial properties. The proposed films have been synthesized by the electrospinning method and are intended to serve as top sheets of sanitary napkins that can easily degrade in the environment. The prepared nanocomposite films of ZnO/curcumin-containing PCL and the pure polymer were characterized using several techniques such as X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and tensile tests. Influence of ZnO/curcumin nanocomposite on the environmental degradability of the electrospun films was studied and an increase in 6% in weight loss was observed due to nanofiller inclusion. Antimicrobial activity increased towards bacterial strain, Staphylococcus aureus by 16 and 18% and fungal strain, Candida albicans by 17 and 21.5% for the ZnO-loaded and ZnO-curcumin-loaded PCL films respectively, compared to neat PCL. In-vitro cytotoxicity of the spun films was evaluated against MC3T3 cell line using MTT assay and cell viability at 72 hours was found to reach 98 and 101% in case of the ZnO and ZnO-curcumin loaded polymer, respectively, indicating cell proliferation and overall biocompatibility. Water permeability and tensile properties of the fabricated films were investigated and compared with those of topsheets of four commercial sanitary napkins to reveal equivalent or enhanced performance. The fabricated polymer composite films are therefore proposed as promising candidates in environmentally degradable non-woven films and can find applications in sanitary napkins, diapers, disposable sheets, etc.