Near‐Infrared‐Irradiation‐Induced Remote Activation of Surface Shape‐Memory to Direct Cell Orientations

Abstract

Here, near‐infrared (NIR) light‐induced remote control of cell morphology is demonstrated. This is enabled by shape‐memory activation of nanopatterns that transition from a memorized temporal pattern to the original permanent pattern. The NIR‐induced shape‐memory nanopatterns are prepared by chemically crosslinking poly(ε‐caprolactone) (PCL) in the presence of gold nanorods (AuNRs). The temporary surface patterns are successfully memorized onto the permanent patterns regardless of the incorporation of AuNRs. Exposure to NIR light can successfully induce the photothermal heating of embedded AuNRs and consequently, the shape‐switching transition to permanent patterns over the melting temperature of PCL. The shape‐memory transition is spatially limited to the photo‐illuminated region, depending on the concentration of embedded AuNRs, the intensity of the NIR light, or the irradiation time. Finally, the NIR‐actuated shape‐memory nanopatterns are used to control cell morphology both remotely and locally. Cells on the illuminated regions change their morphology as the temporal nanopatterns transition to a flat surface. image