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Primary and Secondary Evaluation of Method OMAMAN-05

OMAMAN-05:

DETERMINATION OF BIOTIN IN FORTIFIED BOVINE MILK-BASED INFANT

FORMULA POWDER, FORTIFIED SOYA-BASED INFANT FORMULA POWDER,

FORTIFIED CEREALS, UNFORTIFIED CEREALS, VITAMIN TABLETS AND DIETARY

SUPPLEMENTS BY SURFACE PLASMON RESONANCE: COLLABORATIVE STUDY

Author(s):

Dr. Anthony O'Kane, MSB, Institute for Global Food Security (IGFS), Queens

University Belfast

Primary Reviewer:

Johanna Camara

Secondary Reviewer

: Sawar Gilani

SUMMARY OF METHOD:

This method uses the Biacore Q instrument. The Biacore Q utilizes bio-molecular interaction with anti-

biotin monoclonal antibody and detection by SPR. The Biacore Q uses a fluidics cartridge which consists

of a sensor chip coated with gold, which is turn coated with a dextran hydrogel. When the sample is

introduced into fluidics cartridge, it allows the analyte to pass over the sensor chip. As an inhibition

assay, the excess antibody binds to the biotin-immobilized sensor chip generating the SPR responses,

which is inversely related to the biotin content. The method is an enzymatic and/or autoclave

extraction of biotin from food and vitamin materials followed by dilution and analysis on the Biacore

QTM biosensor instrument (label-free protein binding based assay for surface plasmon resonance).

Quantitative determination of biotin due to SPR response that is proportional to remaining free binding

protein as mixture of biotin extract and excess binding protein binds to immobilized surface of SPR chip.

G

ENERAL

C

OMMENTS

:

The sensitivity of the SPR assay technology coupled with the specificity of the ligand-binding protein

interaction should provide reliable results. However, there is some possibility of non-specific binding

which may result in inaccurate results. The samples should have enough dilution to avoid this possibility.

Therefore, this method may not be robust enough like other established methods and one can get

unpredictable results once a while. When reviewing this method against the specifications found in

Appendix D, it appears that the study contains the appropriate number of labs (11) and studies an

appropriate number of samples (9 blind duplicates) and that the samples represent a variety of types

(commercial products, reference materials, and blanks). The study also included a variety of

international laboratories (service, government, corporate, etc.)

P

ROS

/S

TRENGTHS

:

This method is rapid (11 hours for up to 40 samples) compared to traditional microbiological methods,

which can take 2-3 days. It is a cost-efficient assay in laboratories in developed countries and correlates

well with the established microbiological assay (R2 = 0.9805).

ERP PROFILE SUMMARIES

192