Photo-Activatable Substrates for Site-Specific Differentiation of Stem Cells.

In this report, a UV sensitive, PEGylated PFSSTKTC (Pro-Phe-Ser-Ser-Thr-Lys-Thr-Cys) peptide was modified on quartz substrate to investigate the spatial controlled differentiation of stem cells. This substrate could restrict the cell adhesion due to the steric hindrance of PEG shell. With UV irradiation, PFSSTKTC became exposed owing to the breakage of o-nitrobenzyl group with the detachment of PEG shell. The irradiation boundary on substrate was stable in the long term. The in vitro osteogenic differentiation results revealed that under the site-specific irradiation, the mesenchymal stem cells (MSCs) could specifically differentiate into osteoblast under the induction of PFSSTKTC peptide. This photoactivatable biomaterial shows great potential for region controllable and precise MSCs differentiation.