Noninvasive Photodetachment of Stem Cells on Tunable Conductive Polymer Nano Thin Films: Selective Harvesting and Preserved Differentiation Capacity

Abstract

Viable mesenchymal stem cells (MSCs) were efficiently and selectively harvested by near-infrared (NIR) light using the photothermal effect of a conductive polymer nano thin film. The poly(3,4-ethylenedioxy thiophene) (PEDOT)-coated cell culture surfaces were prepared via a simple and fast solution-casting polymerization (SCP) technique. The absorption of PEDOT thin films in the NIR region was effectively triggered cell harvesting upon exposure to an NIR source. By controlling the NIR absorption of the PEDOT film through electrochemical doping or growing PEDOT with different thin film thickness from 70 to 300 nm, the proliferation and harvesting of MSCs on the PEDOT surface were controlled quantitatively. This light-induced cell detachment method based on PEDOT films provides the temporal and spatial control of cell harvesting, as well as cell patterning. The harvested stem cells were found to be alive and well proliferated despite the use of temperature increase by NIR. More importantly, the harvested MSCs by this method preserved their intrinsic characteristics as well as multilineage differentiation capacities. This PEDOT surfaces could be used for repetitive culture and detachment of MSCs or for efficient selection or depletion of a specific subset from heterogeneous population during culture of various tissue-derived cells because there were no photodegradation and photobreakage in the PEDOT films by NIR exposure.

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.…”

Photo-Seebeck effect of conjugated polymers

“…[1] The PT effect has been of interest in applications such as near-infrared (NIR) PT ablation, [2] spacecraft thermal controls, [3] solar cells, [4] and non-invasive selective harvesting of stem cells. [5] By taking advantage of their absorption in the NIR region, these materials are applied in dark field viewing applications such as a security cameras, [6] night vision sensors, [7] and optical attenuators. [8] On the other hands, thermoelectric material converts heat into electricity and vice versa through the Seebeck and Peltier effects.…”

Photothermally Induced Local Dissociation of Collagens for Harvesting of Cell Sheets

“…The PEDOTlayer was patterned and cells were successfully cultured on the patterned substrate.C ell sheets of various shapes mirroring the PEDOTp attern could be detached after af ew minutes of irradiation with NIR light. [11][12][13][14] By spatially dissociating collagens through the photothermal effect, we now describe,for the first time,tunable cell-sheet detachment and harvesting from ap oly(3,4-ethylenedioxythiophene) (PEDOT) substrate without achange in the cell morphology.PEDOTwas directly coated onto polystyrene by polymer solution casting to form SP-PEDOT (PEDOT made by solution casting polymerization (SP)). [1][2][3][4] Each triple helixisstabilized by numerous hydrogen bonds and supports cell binding.H owever,t he triple helix of collagens unfolds upon heating.…”

“…[5] Therefore,c ontrolling the dissociation of collagen could be highly important for cell-to-surface interactions and eventually for the detachment of cells.Most celldetachment studies are undertaken using temperatureresponsive culture dishes on which thermoresponsive polymers,s uch as poly(N-isopropylacrylamide) (pNIPAAm), are covalently grafted. [11][12][13][14] By spatially dissociating collagens through the photothermal effect, we now describe,for the first time,tunable cell-sheet detachment and harvesting from ap oly(3,4-ethylenedioxythiophene) (PEDOT) substrate without achange in the cell morphology. [11][12][13][14] By spatially dissociating collagens through the photothermal effect, we now describe,for the first time,tunable cell-sheet detachment and harvesting from ap oly(3,4-ethylenedioxythiophene) (PEDOT) substrate without achange in the cell morphology.…”