Comprehensive Characterization of Solution-Cast Polycaprolactone/MXene/Gelatin Composite Films for Biomedical Applications.

Despite significant advances in the development of biocompatible platforms, such as scaffolds, films, and hydrogels, a challenge remains in formulating films with the right balance of mechanical properties and bioactivity. Herein, we developed biocompatible composite films based on polycaprolactone (PCL), MXene, and gelatin that can be utilized for biomedical applications. PCL and gelatin (from bovine, fish, and porcine skin) were used to design the biocompatible matrix, while MXenes were used as a filler to enhance the mechanical and biological properties of the films. We investigated the influence of these three types of gelatin on the chemical structure, morphology, physicochemical properties, cytotoxicity, biocompatibility, and cell growth. All the films exhibited high tensile strength, ranging from 5 to 10 MPa. The incorporation of a relatively small content of MXene (0.5 wt%) altered the tensile properties of the films with the lower gelatin contents (12-15 wt%). SAXS analysis revealed that the nanometer-scale lamellar stack structures characteristic of PCL, consisting of alternating crystalline and amorphous lamellae, were present in all samples and exhibited a morphology identical to that of neat PCL. In contrast, WAXS showed that the relative intensities of individual PCL reflections varied with sample composition, indicating a preferential orientation of PCL crystallites-and consequently of the lamellar stacks-particularly, in MXene-containing samples. The SEM/SE micrographs displayed a coarse morphology of gelatin nanoparticles in the PCL matrix, and the structure coarseness decreased in the following order: PCL/MX/fish gelatin > PCL/MX/bovine gelatin > PCL/MX/porcine gelatin. In vitro, cell culture experiments with SAOS-2 cells revealed that cell confluence was relatively high on samples with the 14.5 wt% porcine gelatin.