4.9. Scanning Electron Microscopy (SEM) Observation

Overnight MRSA USA300 was diluted and then incubated with nortriptyline/amoxicillin alone or their combination at 37 °C for 4 h. The bacteria were collected, washed, centrifuged, and resuspended in 2.5% glutaraldehyde. The samples were then observed for morphological changes using a Sigma 300 scanning electron microscopy (ZEISS, Oberkochen, Germany).