The Invitrogen Countess 3 Standard Slide is optimized for both brightfield and fluorescent counting applications when using Countess II, Countess II FL, Countess 3, or Countess 3 FL automated cell counters. The Countess 3 Standard Slide contains a unique, inert, immobilized bead mixture that mimics the staining pattern of live and dead cells stained with trypan blue under brightfield illumination (the most common cell counting analysis method).

The Countess 3 Standard Slide offers further utility by containing two populations of fluorescent beads that cover the fluorescent spectrum from blue to far red, thereby allowing analysis with a variety of EVOS light cube combinations available to Countess II FL and Countess 3 FL users.

• Accurate—helps eliminate the error involved in creating standard solutions and dilution series
• Flexible—optimized for use in both Countess II, Countess II FL, Countess 3, and Countess 3 FL automated cell counters
• Fast—supplied as a pre-loaded, immobilized, bead suspension; no mixing required
• Convenient—one standard slide for brightfield and fluorescent counting applications

Count confidently
The Countess 3 Standard Slide is supplied ready-to-use and does not require any special handling or sample preparation, thus eliminating the major source of count-to-count variability. Repeatable counts are easily achieved over the life of the slide, with variability only encountered upon changing instrument gating settings, which is very common in multi-user laboratories.