AOAC ERP Gluten Assays - Dec 2018

All other materials were not checked for homogeneity before sending them to the participants. Since it

is known that gluten is not homogeneously distributed in oats, it was decided to include this uncertainty

into the total precision estimates. By doing this a more realistic value will be obtained.

Presentation of Samples to Labs

Following the collaborative test guidelines of AOAC International, two blinded replicates for each sample

were provided to each participating laboratory. The samples were marked with a laboratory-specific

letter (A to U) and a randomized number from 1 to 42. Each laboratory obtained its own coding

(different randomized numbers for each laboratory).

Method and Measurement of Samples

The method was written in AOAC International style and was provided to each lab with the instructions

to follow the method as written with no deviations. Before analyzing the blind-coded samples, each

participant was asked to become familiar with the test method by analyzing three control samples and

the test kit dilution buffer. All OD values obtained had to be recorded in a ready-to-use Excel sheet. The

final data from the laboratories were sent to the study director. The participants were advised to

analyze sample 1 to 21 in run 1 while samples coded 22 to 42 were analyzed in run 2. To ease the

calculation later on, the participants were asked to use a fixed pipetting scheme on the microtiter plate.

Method

AOAC Official Method ####.##

Gluten from wheat, rye, and barley in oats and oat products

by Quantitative sandwich ELISA RIDASCREEN® Total Gluten

Proposed First Action 2018

A. Applicability Statement

RIDASCREEN® Total Gluten is a sandwich enzyme immunoassay to quantify gluten proteins from wheat, rye, and barley in oat and oat products within a measurement range from 5 mg/kg to 80 mg/kg. The assay calibrators were made from a total gluten extract of four wheat cultivars. Results are traceable to the reference oat samples described in AOAC SMPR 2017.021.

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