Pipette-like action of a reusable and NIR light-responsive film for the aspiration and removal of viable cancer cells

Abstract

Achieving the dynamic regulation of cell–surface interactions is particularly attractive for tissue engineering and cell-based treatment. Herein, we report a bottom-up approach for the generation of near-infrared (NIR)-controlled supramolecular “Pipette Device” on a flexible, freestanding poly(dimethylsiloxane)/upconversion nanoparticle (PDMS/UCNP) composite membrane to capture/release cells. Azobenzene (azo) multilayers are constructed on PDMS, connecting β-cyclodextrin monothiol (SH-β-CD) and the anti-epithelial-cell adhesion-molecule (EpCAM) antibody. Biocompatible NIR light is used to excite UCNPs and is converted into local UV light, leading to a rapid release of the cells via the trans–cis isomerization of the azo units. Specifically, this process results in a rapid release of an entire cell-antibody-streptavidin complex from the functionalized surface, without disrupting the cell–surface receptor. Multimaterial systems contribute a functional combination of optical conversion and capture/release, in which PDMS membrane serves as a “firewall” to separated UCNPs and the photo-responsive coating. Such a design can effectively avoid unwanted non-antibody-based capture and local over-heating, thereby achieving a high release efficiency and cell viability. Most importantly, the composite membrane allows the reloading of the antibodies for further cancer cell capture and repeated application of these “pipettes” has no obvious influence on their efficiency. This dynamic control of cell adhesion/release via such a “firewall” approach may offer a new inspiration for functional nano-biointerfaces.