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Price of the test:

$250 per analysis

Acceptable Matrices:

cereal grains, doughs, pastas, and vegetables

Limit of Detection:

835 Units/g

Limit of Quantitation:

2783 Units/g

Sample Size Requirements:

20 grams


UV/Vis spectrophotometer, homogenizer, microplate reader

Reportable Units:

units per gram
One unit of enzyme catalyzes the cleavage of 1 µmole of substrate per minute under the assay conditions (pH 8.5)

Turn Around Time:

15 business days

Is Rush Available?


Method Reference:

BioAssay Systems Lipase Assay Kit (DLPS-100)

Method Description:

Samples are homogenized in a cold phosphate buffered saline solution (PBS), pH 8.5 and then centrifuged.  A protein determination by the Method of Bradford is performed on the enzyme extract (supernatant) to normalize subsequent enzyme results to the efficiency of the protein extraction.  The enzyme extract is incubated at 37C with a saturating amount of triglyceride that contains sulfhydryl groups substituted for the normal carboxylic acid groups on the fatty acids.  As the extracted lipase in the supernatant cleaves the modified fatty acids from the glycerol backbone, the sulfhydryl groups are made available for reaction with a color reagent (DTNB).  The color reagant absorbs visible light at 412nm in direct proportion to the number of sulfhydryl groups exposed by the lipase.  The appearance of absorbance with time of reaction is monitored kinetically.  The initial velocity of the reaction is determined from the reaction rate.

Information Required by Submitter:

Estimates of activity if available
Composition of sample matrix

Additional Information:

Please keep and ship samples frozen when possible.