An Alternative Approach to Plastic Recycling: Fabrication and Characterization of rPET/CA Nanofiber Carriers to Enhance Porcine Pancreatic Lipase Stability Properties.

In response to the increasing demand for sustainable technologies, this study presents a novel approach to plastic recycling. In this study, a method was presented to produce nanofiber carriers by electrospinning using recycled poly(ethylene terephthalate) (rPET) obtained from wastewater bottles and cellulose acetate (CA). These carriers serve as a platform for immobilized porcine pancreatic lipase (PPL), aiming to enhance its stability. The production parameters for the rPET/CA nanofibers were found to be an rPET concentration of 15% (v/v), a CA concentration of 6% (v/v), an electrical voltage of 13 kV, a needle-collector distance of 18 cm, and an injection speed of 0.1 mL/h. The nanofiber structure and morphology were assessed by using attenuated total reflectance-infrared Fourier transform infrared (ATR-FTIR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM) analyses. Then, PPL was immobilized onto the nanofibers through adsorption and cross-linking methods. The optimum temperature for free PPL was determined to be 30 °C, and the optimum temperature for PPL immobilized on rPET/CA was determined to be 40 °C. It was observed that, especially under acidic conditions, after the immobilization process, PPL immobilized rPET/CA nanofibers became more resistant to pH changes than free PLL. Furthermore, the immobilized PPL exhibited improved pH stability, reusability, and thermal stability compared to its free counterpart. This innovative approach not only contributes to plastic waste reduction but also opens new avenues for enzyme immobilization with potential applications in biocatalysis and wastewater treatment.