Aluminum sem stubs

Using similar conditions as previously reported [18 (link),19 (link),21 (link),24 (link),25 (link),26 ,27 (link)], scanning electron microscopy (SEM) of the Lactomorphin and Trehalose (as supplied by the manufacturer), SD, and co-SD powders were evaluated. Visual imaging, analysis of particle size, morphology, and surface morphology were achieved by (SEM). Powder samples were attached to aluminum SEM stubs (Ted-Pella, Inc., Redding, CA, USA) using double-sided carbon conductive adhesive Pelco tabs^™ (TedPella, Inc., Redding, CA, USA). Subsequently, the powder sample in the stub was sputter-coated with a 7 nm thin film of gold using Anatech Hummer 6.2 (Union City, CA, USA) system at 20 μA for 90 s under an argon plasma. SEM images of the powder sample were collected using a FEI Inspect S (FEI, Hillsboro, OR, USA). Images were collected using a tungsten source at 30 kV with a working distance of 10–10.4 mm. SEM images were captured at several different magnification levels.

Prior to SEM, fiber scaffolds were mounted on aluminum SEM stubs (Ted Pella) with conductive carbon tape (Ted Pella) and sputter coated with a 0.5 nm Au/Pd coating using a Hummer Technics V sputter coater (Anatech Ltd.). Fiber samples were then imaged using a FEI Versa 3D DualBeam SEM with a low accelerating voltage (2–10 kV) to avoid melting the fibers.

Nanoparticle size and surface morphology was visualized using SEM (FEI Inspect S SEM, FEI Company, Hillsboro, OR, USA). Powders were deposited on double-sided carbon conductive adhesive tabs (Ted-Pella, Inc., Redding, CA, USA) attached to aluminum SEM stubs (Ted-Pella, Inc., Redding, CA, USA) and sputter-coated (Anatech Hummer 6.2, Union City, CA, USA) with gold for 90 s under argon plasma as previously reported [39 (link)].