An Experimental Model: Modifications of the Chemical Silicone Medical Characteristics for an Improved Biocompatibility

OBJECTIVE: Despite its good biocompatibility and processability, the severe surface hydrophobicity of polydimethylsiloxane (PDMS) limits its biomedical applications. This study aimed to enhance the surface properties of PDMS by depositing gelatin onto it via polydopamine (PDA) mediation and to evaluate the resulting cell-material interactions. METHODS AND RESULTS: The 1% gelatin-modified PDA-PDMS (G-PDA-PDMS) group showed the highest cell viability at 48 h. Surface hydrophilicity was significantly improved, with the contact angle reduced to 21.97° ± 2.06 (p <0.01). XPS confirmed successful modification, showing increased nitrogen signal and characteristic C=O/C-N peaks on G-PDA-PDMS. AFM revealed significantly higher surface roughness and altered nano-topography compared to PDMS (p <0.05). After interacting with cells, it was observed that the cell viability of G-PDA-PDMS was significantly higher than that of the other two groups (p <0.05). FITC/DAPI fluorescence staining showed that the number of cells in G-PDA-PDMS was higher than that in PDMS (p <0.05), and it exhibited a better cell spreading area (p <0.05). Calcein AM/PI fluorescence staining showed that the proportion of red fluorescence in PDA-PDMS and G-PDA-PDMS decreased significantly, while the green fluorescence increased significantly, indicating that they had a better cell survival rate compared with PDMS (p <0.05). The cell scratch test showed that the cell migration rate of G-PDA-PDMS was higher than that of PDA-PDMS (p <0.05). At the molecular level, G-PDA-PDMS significantly upregulated the mRNA expression of TGF-β1, COL3A1, COL1A1, and α-SMA (p <0.05), which was corroborated by increased TGF-β1 protein production (p <0.05). CONCLUSION: Gelatin was successfully modified onto PDA-PDMS. The resulting G-PDA-PDMS material significantly improves surface hydrophilicity, enhances fibroblast proliferation and adhesion, and upregulates key extracellular matrix-related gene and protein expression, demonstrating excellent bioactivity and potential for biomedical applications. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable.