Use of alpha cyclodextrin to eliminate interference by nonesterified fatty acids in calcium measurements

This study shows that nonesterified fatty acids cause underestimation of serum calcium by some colorimetric methods. The underestimation of calcium occurs infrequently, but can be as large as 20-30 mg/l. Preincubation of the sample with alpha cyclodextrin will eliminate this interference. The procedure is simple, inexpensive, and applicable to most clinical laboratories.