Nucleofection
cells were transfected using the Amaxa nucleofector II device (Lonza). Cells were re suspended in specific solutions. Briefly, according to amaxa guidelines ,2.5×\(10^{6}\) RPMI-8226 cells were re suspended in 100 μl of Nucleofection buffer solution containing 5μg DNA, and the cells were transfected using Program G-016 of the Nucleofector II and immediately transferred into 6-well plates containing 37 °C pre-warmed culture medium .
Device Design and FabricationMold was fabricated using conventional photolithography techniques. SU-8 2550 negative photoresist was spin coated on silicon wafer and baked. PDMS pre-polymer and the cross linker were mixed at the recommended 10:1 w/w ratio. After pouring the mixture onto the SU-8 master and degassing for 1 h, the mixture was cured at 75 C for 2 h. PDMS moldings were cut and peeled off the masters. The main components of such devices are: (i) inlet and outlet (ii) main channel: a serpentine-like channel, 100µm width and 60 µm height, consisting of turns with length of 12cm.