Michael,
A number of commercial controls are available for Vitamin A and E (Biorad,
Chromsystems) but none appears to exist for beta carotene. In the abscence
of a commercial QC with a quoted value I have evaluated a number of the
commercial QC preparations in use in our laboratories and found one, Biorad
Liquicheck Level 2, which had a beta carotene value of 0.13 umol/L (ie in
the low range) with adequate stability if aliquoted and stored at -80C and
good reproducibility (CV <10%). Unfortunatley I was unable to find a QC
material with a raised beta carotene. The only option in that regard is to
take a large dose of beta carotene (available at any chemist or health food
shop) and collect enough blood to spin and store the plasma!
Hope this has been helpful,
Regards,
Peter Vervaart.
At 16:34 11/01/99 +1000, Michael Freemantle wrote:
>Is there a commercial control (ie lyophilized) available for beta-carotene
>(retinol and alpha-tocopherol would also be convenient but not
>compulsory)? If not what does everyone who uses a HPLC method for the
>determination of Vit A&E and beta-carotene use for a control material?
>Include stability and storage conditions when replying.
>
>Michael Freemantle
>Sullivan Nicolaides Pathology
>PO Box 344
>Indooroopilly Q4068
>Brisbane
>Australia 4068
>
>ph +61 (0)7 33778638
>fax +61 (0)7 38405989
>
>
>
Peter Vervaart BAppSci MAIMS FAACB
Senior Scientist, Gastroenterology and Nutrition
Department of Clinical Biochemistry
Women's and Children's Health Care Network
Flemington Road
Parkville, Victoria, 3052
Australia
Phone: 613-9345 5906
Fax: 613-9349 1819
WWW: www.rch.unimelb.edu.au\biochem\gastro
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