Optical control of adhesion property of magnetic nanosensor using photochromism for effective manipulation and cell injection

Effective manipulation and rapid injection of nanosensor with high cell viability have great significance to biological and biomedical applications such as drug delivery and cells biology. This study presents manipulation of a magnetic nanosensor with a temperature indicator and immobilization onto cell surface using glass nanoprobe by Coulomb's force. The nanosensor is stained by Rhodamine B as the temperature indicator and is contained by lipid layer with Spiropyran (SP), which is a photochromic material. The zeta potential of nanosensor is switched between negative and positive by photo-isomerization of SP. The zeta potential of the liposome is switched to positive by UV illumination and recovered to negative by VIS illumination. The nanosensor is picked up and transported by glass nanoprobe. The positively charged nanosensor is immobilized to the cell membrane since the zeta potential of cell membrane is negative. The immobilized nanosensor can be injected into the cell cytoplasm by local laser heating. We demonstrated the manipulation and injection of the Ø750 nm magnetic nanosensor by the micromanipulator and local laser heating.