process described above. However, electronics was only partially injected through
the needle. Confocalfluorescence microscope was used to image the 3D structure
of the electronics in the glass needle.Image Jwas used to re-slice the 3D recon-
structed images of device in the longitudinal direction by the step of 1μm.
Immunostaining: Cells were fixed with 4% paraformaldehyde (Electron
Microscope Sciences, Hatfield, PA) in PBS for 15–30 min, followed by 2–3 washes
with ice-cold PBS. Cells were pre-blocked and permeabilized (0.2–0.25% Triton
X-100 and 10% feral bovine serum (F2442, Sigma-Aldrich Corp. St. Louis, MO)
for 1 h at room temperature. Next, the cells were incubated with primary antibodies
Anti-neuron specificb-tubulin (in 1% FBS in 1% (v/v)) for 1 h at room temperature
or overnight at 4 °C. Then cells were incubated with the secondary antibodies
AlexaFluor-546 goat anti-mouse IgG (1:1000, Invitrogen, Grand Island, NY). For
counter-staining of cell nuclei, cells were incubated with 0.1– 1 μg/mL Hoechst
34580 (Molecular Probes, Invitrogen, Grand Island, NY) for 1 min.
Fig. 5.5 Bonding process. Schematics (a) and corresponding optical image (b) of bonding.
(I)flexible cable, (II) ACFfilm and (III) unfolded I/O region of device on substrate.cConnection
resistance of ACFfilm bonded byflipchip bonder (red) and home-made bonding system (blue).
dStatistic results of connection resistance data in (c), showing the average value and standard
deviation
76 5 Syringe Injectable Electronics