Clinical Chemistry AACC Online Job Center
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Clinical Chemistry 21: 134-138, 1975;
This Article
Right arrow Full Text (PDF)
Right arrow Submit an electronic Letter to
the Editor about this paper
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Catalano, E. W.
Right arrow Articles by Solomon, H. M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Catalano, E. W.
Right arrow Articles by Solomon, H. M.

Clinical Chemistry, Vol 21, 134-138, Copyright © 1975 by the American Association for Clinical Chemistry

Measurement of Erythrocyte Glucose-6-Phosphate Dehydrogenase Activity with a Centrifugal Analyzer

Edward W. Catalano 1, George F. Johnson 1, and Harvey M. Solomon 1

1 Department of Laboratory Medicine, The Johns Hopkins Hospital, Baltimore, Md. 21205.

We describe two improved methods for determination of erythrocyte glucose-6-phosphate dehydrogenase activity. One method is an"enzyme-linked" procedure in which an excess of 6-phosphogluconate dehydrogenase is used to produce two moles of NADPH for each mole of glucose-6-phosphate oxidized. In the other method 2,3-diphosphoglycerate is used to inhibit the variable contribution of endogenous 6-phosphogluconate dehydrogenase to glucose-6-phosphate dehydrogenase activity in erythrocyte lysates. These assays require 100 µl of blood and are performed on a centrifugal analyzer in a final reaction volume of 410 µl at 37 °C. NADPH formation is monitored at 340 nm. Hemoglobin is measured as oxyhemoglobin in the same reaction mixture used to determine enzyme activity by changing the wavelength to 550 nm. Results are expressed as international units of glucose-6-phosphate dehydrogenase activity per gram of hemoglobin. The coefficient of correlation between "enzyme-linked" assay and "standard" assay was .992, the slope of the regression line was 1.07, and the intercept was at -0.76. When results of the "enzyme-linked" assay were compared to those of the "nonlinked" assay with added 2,3-diphosphoglycerate, the slope of the regression line was .994, the intercept 0.109, and the correlation coefficient .994.


Key Words: hemoglobin measurement • NADPH formation

Submitted on July 22, 1974
Accepted on October 23, 1974






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1975 by the American Association for Clinical Chemistry.