Dr. Yan Nie (Teltow, DE), Dr. Yue Liu (Teltow, DE), Dr. Xun Xu (Teltow, DE), Dr. Weiwei Wang (Teltow, DE), Dr. Nico Scharnagl (Geesthacht, DE), Dr. Matthias Heuchel (Teltow, DE), Prof. Dr. Nan Ma (Berlin, DE; Teltow, DE)
Abstract text (incl. figure legends and references)
Question: Polydopamine (PDA) gains significant attention for biomedical applications, which conventionally is generated via the polymerization of dopamine and deposits onto substrate [1]. Recent studies show that PDA films can be formed at the air/liquid interface, which can be transferred onto substrates [2]. The potentials of PDA films for guiding cell behaviors were explored by investigating the physical, chemical, and bioinstructive properties of the PDA film, compared to the PDA coating. Methods: Dopamine was used as the precursor for the synthesis of PDA, and the resulting PDA materials were collected from either the liquid/solid (coating) or the air/liquid (film) interface. Results: The results showed that the thickness of the PDA coating was ~ 20 nm, while the thickness of the PDA film was ~ 100 nm. Significantly, the top and bottom surfaces of the PDA film possessed distinct properties, including surface roughness, elasticity, adhesion, and surface chemistry, which were characterized by atomic force microscopy (AFM), Raman spectroscopy, and X-ray photoelectron spectroscopy. Of note, the AFM-based single-cell force spectroscopy demonstrated that the bottom surface of the PDA film showed a higher binding affinity to keratinocytes, compared to the PDA coating and the top surface of the PDA film. Consequently, the difference in the cell-PDA adhesion led to changes in the gene expression profiles. Conclusions: PDA materials generated at different interfaces could guide diverse cellular behaviors, demonstrating the ease and versatility of using PDA surface modification to modulate cell functions. Together, developments in PDA-based materials hold great potential to advance fields such as tissue engineering and regenerative medicine.
Reference
[1] J. H. Ryu, P. B. Messersmith, H. Lee, Acs Appl Mater Inter 2018, 10, 7523.
[2] E. Coy, I. Iatsunskyi, J. C. Colmenares, Y. Kim, R. Mrówczyński, Acs Appl Mater Inter 2021, 13, 23113.