Protocol name: Agar slide preparation Prepared by: Monica Ponder Date Created/Revised: 5/27/03 Purpose: To allow visualization of microbial cells by light microscopy so that cells are adhered to the surface and produce less shadow Reference(s): Adapted from advice of Frank Dazzo Comments: Prepare cultures to a very low density, 0.1- 0.2 OD 600, 50 ul spotted onto slide To prepare agar coated slides: Prepare 0.75% Nobel agar (0.375g per 50 mls of MilliQ). Sterilize 25 minutes. To microscope slide add 0.250 mls of melted agar to end of slide and drag another slide across at a 45° angle so that a very thin film of agar is left on the slide. Allow slides to dry under UV light to prevent contamination. Store in sterile Petri dish until ready to use. A good photograph should have at minimum 6 bacteria but no more than 30 per field and have all firmly affixed to slide. Streaks are not good. You should also include a size marker for published photos.