Transmission Electron Microscopy Transmission Electron

							Transmission Electron Microscopy. Gel samples were applied to carbon-coated 200 mesh copper grids and allowed to dry. Prior to examination the gels were shadowed with Pt atoms at angle of 45. Transmission electron micrographs were recorded on a Jeol JSM-1010 instrument. Pt shadowing was performed using an Edwards 306 system.

Scanning Electron Microscopy. Gel samples were applied to stainless steel stubs and allowed to dry. Prior to examination the gels were coated with a thin layer of gold/Pt. Scanning electron micrographs were recorded using a Jeol JSM-6330F instrument. Gold/Pt deposition was performed using a Denton vacuum LLC.

Cryo- Scanning Electron Microscopy. Gel samples were applied to stainless steel stubs and allowed to dry. Prior to examination the specimens were plunged into liquid nitrogen. Specimens were transferred under liquid nitrogen and mounted in a precooled Oxford ALTO 2500 cryo system. Cryo SEM images were recorded at a temperature of -190C.

Atomic Force Microscopy. Samples were analysed by AFM by pipetting a small amount of sample into a Petri dish containing a mica disk, which served as the sample substrate. The petri dish was covered to avoid contamination whilst the sample dried. The gel coated mica disk was mounted on a metal puck for subsequent AFM imaging. The gels were imaged in ambient conditions with a Veeco Explorer AFM. All images were acquired in non-tapping mode using etched silicon probes operated at their fundamental resonance frequencies of 240 – 420 kHz. These 125 m long cantilevers had a nominal force constant (k) of 13 – 100 N/m, a tip radius curvature of ~ 20 nm. Height and amplitude mode images were recorded simultaneously at a scan rate of 200 nm / s for the higher resolution images and 0.5 m / s for the bigger scans. The scan angle was 0.