SEM Imaging of Gold-Coated Biological Samples

All samples were imaged in a JCM-5700 Scanning Electron Microscope (JEOL USA, Peabody, MA, USA) contained inside a mobile biological containment enclosure (Dycor Technologies Ltd, Edmonton, AB, Canada)8 (link). Gold coated specimens were imaged under high vacuum at 6 kV, with an 8 mm working distance and a 30 μm objective lens aperture. Images were collected using the secondary electron detector, the acquisition time per image was 160 sec and each image was 2560 × 1920 pixels. Images of ionic liquid stained samples were obtained using the above noted settings with the exception that the acceleration voltage was adjusted to 4 kV. SEM images were recorded at magnifications ranging from 3,000 x to 20,000x.