High-Preservation Single-Cell Operation through a Photo-responsive Hydrogel-Nanopipette System.

Single-cell and in situ cell-based operation with nanopipette approach offers a possibility to elucidate the intracellular processes and may aid the improvement of therapy efficiency and precision. We present here a photo-responsive hydrogel-nanopipette hybrid system that can achieve single-cell operation with high spatial/temporal resolution and negligible cell damage. This strategy overcomes long-time obstacles in nanopipette single-cell studies as high electric potential (ca. 1000 mV) or organic solvent is always used during operations, which would inevitably impose disturbance and damage to targeted cells. The light-triggered system promotes a potential-free, non-invasive single-cell injection, resulting in a well-retained cell viability (90 % survival rate). Moreover, the photo-driven injection enables a precisely dose-controllable single-cell drug delivery. Significantly reduced lethal doses of doxorubicin (163-217 fg cell-1 ) are demonstrated in corresponding cell lines.