Pressure regulated biomolecule injection into NIH 3T3 cells through integrated nano/mesopores

We describe a proof-of-concept experiment to demonstrate the feasibility of pressure regulated biomolecule injection into cells through a nano/mesopore membrane integrated in a microfluidic device. By using soft lithography, a thin layer of polydimethlysiloxane (PDMS) was patterned on the surface of a commercial polycarbonate (PC) membrane with na-no/mesopores, providing well-defined injection windows. Then, the PDMS-PC thin layer assembly was inserted into a microfluidic device. After NIH 3T3 cell culture, the injection of chemical or bio-molecules into the cells could be performed by regulating the pressure from another side of the membrane. The preliminary results with trypan blue dye injection showed the possibility of precise dose control of the injection through the pore areas. Such an approach should be useful for future studies on nano/mesoscopic cell-material interactions.