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