Figure 1

Rupturing cancer cells using the physical force of expanding stimuli-responsive hydrogels. (a) Scheme illustrating the process in which the cancer cells first attach onto the surfaces of the stimuli-responsive hydrogels. After the hydrogels expand under the influence of an external stimulus (for example, temperature), the cancer cells rupture. (b) Scheme illustrating the surface modification of the hydrogel. The surface was coated first with a layer of polydopamine (PDA) and poly-L-lysine (PLL) and then with a layer of RGD peptides for attaching the cancer cells. (c) Photographs of the temperature-responsive hydrogels (PNIPAM) with or without surface modification at different temperatures. Nascent hydrogels incubated at 22 °C (top left), and at 37 °C (top right); RGD-modified hydrogels incubated at 22 °C (bottom left) and at 37 °C (bottom right). (d) Comparison of the swelling ratio (SR) and (e) the recovery ratio (RR) of the temperature-responsive hydrogels with and without surface modification.