A Poly-L-Lactic Acid Honeycomb Scaffold for Enhanced Cytocompatibility

In this study, we present the development of biopolymer honeycomb (HCP PLLA) microstructures on plasma-modified PTFE polymer using the improved phase separation method with the aim of preparing a surface with enhanced cytocompatibility. To determine changes in surface morphology and characterize the size and shape of the prepared PLLA microstructures, laser confocal microscopy (LCM), atomic force microscopy (AFM), and scanning electron microscopy (SEM) methods were used. To determine the chemical composition of the surface of substrates modified with the formed HCP PLLA microstructures, X-ray photoelectron spectroscopy (XPS) was used. PTFE samples modified with an 8 W plasma discharge proved to be a suitable material for further study as a substrate for honeycomb patterns and biocompatibility testing. It was found that the formation (size) of PLLA microstructures is influenced not only by the exposure time of the samples in plasma but also by the PLLA content in the coating solution and the thermal stress of the material. Plasma modification and subsequent phase separation significantly increased the surface amount of oxygen and carbon and suppress the surface amount of fluorine to a minimum, which is evidence of almost 100% coverage of the PTFE surface with the PLLA coating solution. Biocompatibility testing on selected PTFE samples revealed that modification with 8 W plasma in combination with HCP microstructures—created by the phase separation method in solution with 3 wt. % PLLA—leads to significant support for SaOS-2 osteoblast cell proliferation. This study highlights the potential of biopolymer honeycomb pattern surfaces with engineered topography for advanced biomedical applications.