Spatially selective treatment and collection of 4T1 tumor cells for testing subcellular doxorubicin delivery using the HFSM.

A Low-resolution fluorescence (right) and brightfield (left) images of 4T1 cells after exposure to a stream of doxorubicin for 10 min. Images at the top and bottom were obtained using 5x and 10x dry objectives, respectively. The red fluorescence signal represents doxorubicin internalized in 4T1 cells. B High-resolution fluorescence images of a 4T1 cell suspension collected using spatially controlled trypsin EDTA flow post-exposure to doxorubicin flow. The top and bottom images were acquired using a 63x oil objective and zoom functionality (0.6x and 3x zoom), respectively. The high-resolution images show clear co-localization of the fluorescence signals of DAPI (blue) and doxorubicin (red) in the cell nuclei, verifying nuclear delivery of doxorubicin using the HFSM.