Ammonia Assay Kit

If this product has an expiration or retest date, it will be shown on the Certificate of Analysis (COA, CofA). If there is no retest or expiration date listed on the product's COA, we do not have suitable stability data to determine a shelf life. For these products, the only date on the COA will be the release date; a retest, expiration, or use-by-date will not be displayed.
For all products, we recommend handling per defined conditions as printed in our product literature and website product descriptions. We recommend that products should be routinely inspected by customers to ensure they perform as expected.
For products without retest or expiration dates, our standard warranty of 1 year from the date of shipment is applicable.
For more information, please refer to the Product Dating Information document: https://www.sigmaaldrich.com/deepweb/assets/sigmaaldrich/marketing/global/documents/418/501/product-dating-information-06-25-mk.pdf

This kit has not been tested for its suitability for the detection of ammonia concentration in plant tissues.

A standard curve is not required for this kit. The Ammonia Standard Solution should be included with each set of assays. If the value obtained with the Ammonia Standard Solution is within 5% of the stated concentration, the test performance is acceptable and sample data is valid.

The protocol below has not been tested but is based on adaptations of the reagents to similar instruments.
In order to perform the assay in a microplate instead of cuvettes, the reagent and sample volumes can be reduced by a factor of 5. Thus, the reagent volume would be 200 microliters; the volume of water or sample would be 20 microliters, and the volume of standard would be 10 microliters. The required volume of the enzyme solution would decrease to 2 microliters, which is difficult to pipette accurately. To deliver the enzyme more accurately, dilute it 5x P5244 using Phosphate Buffer, pH 7.5, as the enzyme diluent and pipette 10 microliters into each well.

Products may be shipped at a different temperature than the recommended long-term storage temperature. If the product quality is sensitive to short-term exposure to conditions other than the recommended long-term storage, it will be shipped on wet or dry-ice. If the product quality is NOT affected by short-term exposure to conditions other than the recommended long-term storage, it will be shipped at ambient temperature. As shipping routes are configured for minimum transit times, shipping at ambient temperature helps control shipping costs for our customers. For more information, please refer to the Storage and Transport Conditions document: https://www.sigmaaldrich.com/deepweb/assets/sigmaaldrich/marketing/global/documents/316/622/storage-transport-conditions-mk.pdf

Any sample solution that is strongly colored and/or has a low ammonia concentration should be decolorized when using this kit. Colored sample solutions often are treated with decolorizing carbon (activated charcoal) to remove color-contributing impurities.

A convenient control for use with this kit is the Ammonia Standard Solution that is provided in the kit.

Transportation information can be found in Section 14 of the product's (M)SDS.To access the shipping information for this material, use the link on the product detail page for the product.

Generally, an absorbance change of 0.050 or less indicates an acceptable range for the reagent blank. An absorbance change higher than this indicates possible contamination of the reagent (or glassware) with ammonia.

The basis for this kit was a Diagnostic procedure for the determination of Ammonia in human plasma, whose total protein concentration is approximately 63 to 83 mg/mL. Thus, any solution whose protein concentration is less than approximately 83 mg/mL should not require deproteinization.