Questions and answers

Is resazurin an oxygen indicator?

Is resazurin an oxygen indicator?

After the media was reduced and the resazurin turned into pink and then transparent, you can use it as an indicator for redox/oxygen conditions. So if you need “strict” anaerobic conditions, you must add a chemical that “destroys” all the residual oxygen present.

What triggers resazurin to Resorufin?

Resazurin is effectively reduced in mitochondria, making it useful also to assess mitochondrial metabolic activity. Usually, in the presence of NADPH dehydrogenase or NADH dehydrogenase as the enzyme, NADPH or NADH is the reductant that converts resazurin to resorufin.

Can you autoclave resazurin?

The solution is prepared by autoclaving or momentarily boiling 200 ml of distilled water in a light resistant (amber) stoppered flask and then adding one methylene blue tablet to the flask of hot water. The tablet should be completely dissolved before the solution is cooled.

What color is resazurin when it is oxidized?

8.4. Resazurin assays are based on the reduction by living cells of the oxidized blue dye to a pink fluorescent resorufin product.

Why is resazurin used?

Resazurin is commonly used to measure bacterial and eukaryotic cell viability through its reduction to the fluorescent product resorufin.

How does the resazurin test work?

Resazurin gives milk a characteristic blue colour and the test is based on the ability of bacteria in the milk to reduce the blue dye.

What color is resazurin in the presence and absence of oxygen?

A particularly useful redox color indicator is resazurin in water. This redox indicator is colorless in an atmosphere devoid of oxygen but in an oxygen-containing atmosphere it has a pink color.

What enzyme reduces resazurin?

diaphorase enzymes
Resazurin (blue) diffuses into cells where it is irreversibly reduced by diaphorase enzymes to a highly fluorescent (pink) compound, resorufin.

How much resazurin is added to media?

The final working concentration for Resazurin is 44 uM and our goal is to prepare a 10X solution for use in cell culture (e.g. for 200 ul of media/cells, we will add 20 ul of the dye).

What does resazurin test measure?

The Resazurin test is designed for assessing the quality of raw bulked milk. Resazurin gives milk a characteristic blue colour and the test is based on the ability of bacteria in the milk to reduce the blue dye.

What type of agent is resazurin?

The use of resazurin as a novel antimicrobial agent against Francisella tularensis. The highly infectious and deadly pathogen, Francisella tularensis, is classified by the CDC as a Category A bioterrorism agent.

What is Resazurin test used for?

The Resazurin test is designed for assessing the quality of raw bulked milk. This is essentually a rapid bacteria estimation and can be carried out either as a 10 minute pass or fail, a 3 hour triple reading test or as the standard and generally accepted 1 hour test.

Can you use resazurin as an oxygen indicator?

After the media was reduced and the resazurin turned into pink and then transparent, you can use it as an indicator for redox/oxygen conditions. You should look it up online, but you can make a redox indicator solution, but it needs the addition of a reducing sugar and I believe that it is usually slightly alkaline.

What happens to resazurin in a nitrogen solution?

In these conditions, the small strips of resazurin indicator become colorless. The nitrogen alone, even at high purity, contains always minor amounts of oxygen: the resazurin never will turn colorless if you do not add a compound able to transform the residual oxygen in H20.

How is the reduction of resazurin carried out?

The assay also can be monitored by absorbance although there is a slight loss of sensitivity [1]. Reduction of resazurin is believed to be accomplished by reductase or diaphorase-type enzymes from mitochondria and the cytosol [31].

Why is resazurin used as a viability reagent?

Various formulations of resazurin are becoming more commonly used as viability reagents in drug screening. The original patented commercial product, Alamar Blue, contained resazurin and possibly also a mixture of stabilizer salts to minimize spontaneous background reduction in the absence of cells [1].