Dsx1000 digital microscope

An optical microscope (Olympus DSX1000
digital microscope) is used to image deposited droplets in bright
field mode. The images are acquired at a ×50 magnification. For
the device’s imaging, a single 70 × 70 μm image
is not sufficient to observe the entire device. Therefore, an area
of 7 × 7 images is sequentially taken and stitched together with
a 10% overlap in live panorama mode.

The fabrication of the composite EF-HAM scaffold was performed via electrospinning as previously described with some modifications [14 (link),41 (link)]. Poly lactic-co-glycolic acid (50:50) (PLGA 50:50; DURECT, Birmingham, AL, USA) was dissolved at a 20% (w/v) concentration in a 7:3 solvent mixture containing dichloromethane (DCM; Sigma-Aldrich) and dimethylformamide (DMF; Sigma-Aldrich) and stirred at 230 rpm for 20 h at room temperature. PLGA was then spun onto the decellularized HAM attached to a rotating collector at 7.5 kV of applied voltage, 0.3 mL/h of polymer flow rate, and 15 cm of deposition distance. To study the effect of fiber thickness on the angiogenic potential of EF-HAM scaffolds, different fiber thicknesses were created on HAM by varying the deposition times to 3, 5, and 7 min. Resulting EF-HAM scaffolds were later air-dried under biosafety cabinet and UV-irradiated for 40 min.
The gross morphology and density of PLGA fibers on EF-HAM scaffolds were then observed through images captured using Olympus DSX1000 digital microscope. Prior to any cell culture application, HAM and EF-HAM scaffolds were rehydrated overnight in DPBS with 1% (v/v) AA solution.