Stimuli responsive polymer coatings are a common motive for designing surfaces for cell biological applications. In the present study, we have characterized temperature dependent adhesive properties of poly(N-isopropylacrylamide) (PNIPAm) microgel coated surfaces (PMS) using various atomic force microscopy based approaches. We imaged and quantified the material properties of PMS upon a temperature switch using quantitative AFM imaging but also employed single-cell force spectroscopy (SCFS) before and after decreasing the temperature to assess the forces and work of initial adhesion between cells and PMS. We performed a detailed analysis of steps in the force-distance curves. Finally, we applied colloid probe atomic force microscopy (CP-AFM) to analyze the adhesive properties of two major components of the extracellular matrix to PMS under temperature control, namely collagen I and fibronectin. In combination with confocal imaging, we could show that these two ECM components differ in their detachment properties from PNIPAm microgel films upon cell harvesting, and thus gained a deeper understanding of cell-sheet maturation and harvesting process and the involved partial ECM dissolution.
Bibliographical noteFunding Information:
We thank the Max Planck Society and the MPG fellow program, the Volkswagen Foundation Initiative LIFE (Project Living Foam) and SFB 937 “Collective behavior of soft and biological matter” (Project A8) for funding.
Copyright © 2020 American Chemical Society.
- MDCK II epithelium
- atomic force microscopy (AFM)
- cell-sheet harvesting
- colloidal probe atomic force microscopy (CP-AFM)
- poly(N-isopropylacrylamide) (PNIPAm)
- single-cell adhesion force spectroscopy (SCFS)
ASJC Scopus subject areas
- Materials Science(all)