Influence of Temperature on the Delta pH Method of Measuring Blood Cholinesterase.
Abstract
Efforts to evaluate the precision of the Michel delta pH method of measuring cholinesterase activity, performed in a breaker immersed in a 25C water bath, resulted in unexpected variability in results of day-to-day replicate analyses. Most disturbing was the considerable variation between each 4-hour period of an 8-hour day (a.m. and p.m. measurements). Precision of quadruplicate sets, expressed as coefficient of variation, ranged from plus or minus 0.5% to 8.0%. By rigidly controlling temperature with a water-jacketed reaction vessel, the variation was reduced to plus or minus 1.7%. A study of the effect of temperature on the method showed that a 1-degree change in temperature resulted in a 5.5% change in plasma activity and a 3.0% change in red cell activity. A graphing of the influence of temperature on reaction rate produced a linear relationship. Identical thermodynamic data were obtained with plasma and red cell samples which were inhibited 50% with an with an irreversible anticholinesterase agent. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1974
- Accession Number
- AD0787314
Entities
People
- Pasquale P. Vicario
- Robert I. Ellin