Details

Autor(en) / Beteiligte

• Baadenhuijsen, H
• Demacker, P N
• Hessels, M
• Boerma, G J
• Penders, T J
• Weykamp, C
• Willems, H L

Titel

Testing the accuracy of total cholesterol assays in an external quality-control program. Effect of adding sucrose to lyophilized control sera compared with use of fresh or frozen sera

Ist Teil von

• Clinical chemistry (Baltimore, Md.), 1995-05, Vol.41 (5), p.724-730

Ort / Verlag

England

Erscheinungsjahr

1995

Quelle

MEDLINE

Beschreibungen/Notizen

• We studied the suitability of various types of human serum preparations to test the accuracy of total cholesterol measurements in the External Quality Assessment scheme in The Netherlands, in which approximately 180 laboratories participate. Checked against the certified Abell/Kendall Reference Method, large reagent-dependent negative biases were observed with lyophilized serum that was insufficiently cryoprotected. The biases for the reagents of Du Pont, Roche, and Beckman averaged -16.7%, -9.2%, and -7.6% respectively; the least bias, -0.4%, was obtained with reagent from Boehringer Mannheim. The beneficial effect of cryoprotection with sucrose was demonstrated by the decrease in interreagent variation from 5.4% to 1.9%, the latter value being comparable with the values for fresh and once-frozen pooled serum (1.3% and 1.7%, respectively). We conclude that the detrimental effect of lyophilization on serum matrix can be minimized by suitable cryoprotection with 200 g/L sucrose.