K575x high resolution sputter coater

An aliquot of bacterial culture growing statically was carefully pipetted and gently placed onto a Sterlitech PETE membrane filter and incubated for 2 hours without disturbance or vacuum, allowing the bacteria to settle on the substrate and maintain the structural integrity of the fine fimbriae. The samples were covered to prevent contamination and drying out. The samples were then fixed in a cocktail of 4% formaldehyde and 2% glutaraldehyde in 0.1M cacodylate buffer and subsequently post-fixed using a 1% osmium tetroxide solution. They were then dehydrated in a series of graded alcohols ranging from 35% to 100% with the final dehydration completed using a Tousimis (Rockville, MD) critical point dryer. The dried samples were then coated with a thin layer of iridium using an EMITECH K575X high-resolution sputter coater and imaged with the Zeiss 450 FE-SEM (Oberkochen, DE) at 1.50kV using the InLens SE detector.