Objective: To explore the effect of different functional groups on self-assembled monolayers on the biological characteristics of rabbit skeletal muscle cells in vitro.
Methods: Rabbit skeletal muscle cells were cultured on self-assembled monolayers of gold on which different terminal chemical groups including methyl groups (-CH(3)), amino(-NH(2)), hydroxyl(-OH) and carboxyl (-COOH ) were anchored with self-assembled methods. Contact angle measurements and atomic force microscopy were employed to confirm the similar density of different functional groups occupation. Fluorescence microscopy, MTT assay, flow cytometry, and scanning electron microscopy (SEM) were used to analyze the morphological and biological alterations of the cells.
Results: SEM results revealed that the chemical groups on the surface of the monolayer modulated the structure of skeletal muscle cells and the cell morphology. Skeletal muscle cells cultured on the monolayer with -CH3 exhibited the smallest contact area with a spherical morphology, while the cells on the monolayers with -NH(2), -OH and -COOH showed much larger contact area and flatter morphology. The functional groups -NH(2) and -COOH obviously promoted cell adhesion and proliferation, while -CH(3) group produced significantly greater toxicity than -NH(2), -OH and -COOH groups to inhibit the cell growth and adhesion and promote cell death. Cell attachment and growth was enhanced, in the order the magnitude of the effect, by -NH(2)>-COOH>-OH>-CH(3), and the toxicity decreased in the order of -NH(2)>-COOH>-OH>-CH(3).
Conclusion: The terminal chemical groups can obviously affect the phenotype of skeletal muscle cells in vitro, and this finding provides a theoretical basis for surface design of biomaterials.