Chen W, Zhang Y, Kumari J, Engelkamp H, Kouwer PHJ. Magnetic Stiffening in 3D Cell Culture Matrices.
NANO LETTERS 2021;
21:6740-6747. [PMID:
34387494 PMCID:
PMC8392345 DOI:
10.1021/acs.nanolett.1c00371]
[Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 08/09/2021] [Indexed: 05/15/2023]
Abstract
The mechanical environment of a cell is not constant. This dynamic behavior is exceedingly difficult to capture in (synthetic) in vitro matrices. This paper describes a novel, highly adaptive hybrid hydrogel composed of magnetically sensitive magnetite nanorods and a stress-responsive synthetic matrix. Nanorod rearrangement after application of (small) magnetic fields induces strain in the network, which results in a strong (over 10-fold) stiffening even at minimal (2.5 wt %) nanorod concentrations. Moreover, the stiffening mechanism yields a fast and fully reversible response. In the manuscript, we quantitatively analyze that forces generated by the particles are comparable to cellular forces. We demonstrate the value of magnetic stiffening in a 3D MCF10A epithelial cell experiment, where simply culturing on top of a permanent magnet gives rise to changes in the cell morphology. This work shows that our hydrogels are uniquely suited as 3D cell culture systems with on-demand adaptive mechanical properties.
Collapse