Carbon Nanotube Monolayer Patterns for Directed Growth of Mesenchymal Stem Cells

Abstract

Herein, wereport a method to control the adhesion and shape of MSCsusing monolayered CNT patterns. As a proof of concept, wepatterned various 1D nanostructures, including CNTs andNWs, on substrates, and MSCs were subsequently culturedand observed on the patterned substrates. In this work, self-assembled monolayer (SAM) patterns were first used todirect the assembly of single-walled CNTs (swCNTs) andmulti-walled CNTs (mwCNTs) on solid substrates. A self-limiting mechanism ensured the assembly of only a singlelayer of CNTs, without significant change of surface morphol-ogy. Importantly, the MSCs exhibited preferential growth onCNT patterns, and the cell culture results suggested that theCNT patterns did not have a harmful effect on the MSCs.Further, we demonstrated the growth of MSCs on swCNTpatterns between electrodes. These results clearly show thatCNT patterns have enormous potential as a new platform forbasic research and applications using stem cells.Figure 1 shows a schematic diagram depicting our experi-mental procedure for directed MSC growth. First, a non-polarSAM of 1-octadecanethiol (ODT) was patterned, while leav-ing some bare Au regions (Fig. 1A). SAM patterning on Aucan be achieved using dip-pen nanolithography (DPN)