Photothermally Induced Local Dissociation of Collagens for Harvesting of Cell Sheets

Abstract

The local heating of poly(3,4-ethylenedioxythiophene) (PEDOT) by a photothermal effect directed by near-infrared (NIR) light induces unfolding of absorbed collagen triple helices, yielding soluble collagen single-helical structures. This dissociation of collagens allowed the harvesting of a living idiomorphic cell sheet, achieved upon irradiation with NIR light (λ=808 nm). The PEDOT layer was patterned and cells were successfully cultured on the patterned substrate. Cell sheets of various shapes mirroring the PEDOT pattern could be detached after a few minutes of irradiation with NIR light. The PEDOT patterns guided not only the entire shape of the cell sheets but also the spreading direction of the cells in the sheets. This photothermally induced dissociation of collagen provided a fast non-invasive harvesting method and tailor-made cell-sheet patterns.

Near-infrared light-responsive hydrogels via peroxide-decorated MXene-initiated polymerization

“…"Smart" responsive hydrogels are now being widely studied in various elds such as so robotics, 1,2 sensors, 3,4 microdevices, 5 drug delivery, 6,7 cell/tissue engineering scaffolds, 8,9 and reaction vessels. 10,11 Exposure to different stimuli (for example light, temperature, pH, and electric eld) may cause these hydrogels to swell/shrink, bend/unbend, or swim/crawl, mimicking natural creatures with responsive behavior.…”

Facile Cell Sheet Harvest and Translocation Mediated by a Thermally Expandable Hydrogel with Controlled Cell Adhesion

“…[2] The cell sheet was originally harvested from a poly(N-isopropylacrylamide) (PNIPAAm)-grafted surface; the phase transition from hydrophobic to hydrophilic below the lower critical solution temperature enables the cell sheet detachment. [3] Other substrates responding to stimuli including enzyme, [4] pH, [5] electricity, [6] and light [7,8] have been developed to harvest cell sheets maintaining cell-cell contact with intact extracellular matrix (ECM). However, the detachment time varies depending on cell types and grafting density of PNIPAAm on the surface, which is sometimes hard to be controlled in the laboratory.…”

Construction of a photothermal Venus flytrap from conductive polymer bimorphs

“…The photothermal properties of CPs have been intensely investigated only in the fields of photothermal energy harvesting and cell engineering. [21][22][23][24][25][26] Therefore, the application of highly photothermal CPs, such as PEDOTs, into foldable bimorphs is an interesting challenge. The other challenge is the fabrication of bimorphs with CPs, which involves the transfer of a CP layer onto a soft layer.…”

“…28,29 Furthermore, the PEDOTs with tosylate dopants have high photothermal properties in a thin-film state (sub-micron level). 24,25 Such one-step film preparation from EDOT and the high electrical conductivity plus photothermal properties of the film could be advantages for PEDOT as an active bimorph over other materials. 7,30,31 To transfer the PEDOT layer directly onto a soft PDMS layer, a dry transfer method could be explored and used to take advantage of the curing-induced detachment properties of the PDMS surface.…”