Using microfabrication and electrostatic layer-by-layer (LbL) self-assembly technologies to improve the growth and alignment of smooth muscle cells

Smooth muscle cells (SMCs) were cultured on polydimethylsiloxane (PDMS) based cell culture substrates. Two types of experiments were performed to address the cell behaviors on these substrates. One was culturing smooth muscle cells on bare PDMS flat surfaces and gelatin coated PDMS flat surfaces deposited using electrostatic layer-by-layer self-assembly technology. The other was culturing smooth muscle cells on two microstructured PDMS microchannel substrates and PDMS flat surface substrates. The microchannels are 5-μm channels (line width = 5 μm, spacing width = 5 μm, depth = 5 μm) and 100-μm channels (line width = 100 μm, spacing width = 100 μm, depth = 50 μm) respectively. All substrates were coated with multilayers (50 nm in thickness) of gelatin using electrostatic layer-by-layer self-assembly technology in order to improve the attachment of the cells. We concluded that surface treatment, such as gelatin coating, is able to help smooth muscle cells attach on PDMS substrates. Accordingly, it will increase the potential growth of cells on the engineered PDMS substrates. Second, smooth muscle cells showed a clear preference of alignment long the channel sidewall on the 100-μm channel substrate as compared to that on the flat surface substrate. Microchannels are able to align the growth of smooth muscle cells, and the ability of controlling the alignment depends on the dimension of the microstructures, as well as the surface treatment for increasing cell attachment. Microfabrication and electrostatic layer-by-layer self-assembly technologies have significant potential for application in the field of tissue engineering