Spatially controlled multicellular differentiation of stem cells using triple factor-releasing metal-organic framework-coated nanoline arrays.

Improved in vitro models are needed for regenerative therapy and drug screening. Here, we report on functionally aligned nanoparticle-trapped nanopattern arrays for spatially controlled, precise mesenchymal stem cell differentiation on a single substrate. The arrays comprise nanohole and nanoline arrays fabricated through interference lithography and selectively capture of UiO-67 metal-organic frameworks on nanoline arrays with a 99.8% efficiency using an optimised asymmetric spin-coating method. The UiO-67 metal-organic frameworks contain three osteogenic differentiation factors for sustained release over four weeks. The combination of differentiation factors and patterned array allows for generation of adipocytes, osteoblasts, and adipocyte-osteoblast mixtures on nanohole arrays, nanoline arrays, and at the nanohole-nanoline interface, respectively, with mature osteoblasts exhibiting higher marker expression and mineralisation. The sustained release patterned array holds potential for constructing advanced therapeutic and disease state in vitro cellular models.