Microbiological Analysis Support—Getting Started

Many dyes that are used on mammalian cells have also been shown to be useful in bacterial cells. For example, CellROX™ Deep Red Reagent has been shown to work in B. subtilis (see Reference). If you are interested in a particular dye, but are not sure if it will work on your bacteria, literature searches are the best way to check to see if it has been tested. If not, then it may be worth testing yourself. 

There are several options. We have two fluorescence based kits that are useful for bacterial counting: Live/Dead™ BacLight™ Bacterial Viability and Counting Kit, for flow cytometry (Cat. No. L34856) and Bacteria Counting kit, for flow cytometry (Cat. No. B7277). Another option is the Flow Cytometry Sub-micron Particle Size Reference Kit (Cat. No. F13839).

We offer a number of kits for food and water testing, including solutions for E. coli, Salmonella, Listeria, Cryptosporidium, and Giardia testing. Visit our website and browse in the Food Safety and Animal Health application areas under Applied Sciences.

Dynabeads™ magnetic beads microbiology enrichment products offer the following advantages: 

• Simple protocol
• Cost effective
• Shelf-stable reagents
• Easy QC
• High sensitivity
• Saves time (for Salmonella in processed food, the assay is 24 hours faster compared to standard methods because immunomagnetic separation (IMS) replaces conventional selective enrichment; also saves time in confirmation procedure because you already have the colony isolated)

Platelet cells don‘t have DNA, while bacteria do. Therefore, a cell-permeant, DNA-selective dye would preferentially stain the bacteria with limited staining of the platelets. We recommend using Hoechst™ 33342 dye.