Plasma cholinesterase phenotyping with use of visible-region spectrophotometry.

Plasma cholinesterase phenotyping with use of visible-region spectrophotometry.

A method that overcomes the difficulties of the 240-nm benzoylcholine method for phenotyping plasma cholinesterases has been developed. After a timed reaction, under the same reaction conditions as in the classic procedure, choline is detected at 500 nm by use of choline oxidase coupled with the peroxidase/phenol/aminoantipyrine system. Cholinesterase activity measurements, calibrated by use of...

Derivative ultraviolet-visible region absorption spectrophotometry and its analytical applications.

Theoretical aspects, instrumental devices and analytical applications of derivative ultraviolet-visible region absorption spectrophotometry are reviewed.

Basic UV/Visible Spectrophotometry

Interlaboratory study of the proficiency of cholinesterase phenotyping.

We report the results of a proficiency survey into the accuracy of cholinesterase (EC 3.1.1.8) phenotyping undertaken by 12 laboratories over a three-year period, during which 21 samples of nine different genotypes were analyzed. Specimens from patients who were homozygous for the atypical variant AA or from UA and AF heterozygotes were identified without difficulty, but the less-well-recognize...

Morphologic phenotyping with MR microscopy: the visible mouse.

A method for rapid morphologic phenotyping is demonstrated by using magnetic resonance microscopy. Whole fixed C57BL/6J mice were imaged at 110-microm isotropic resolution; limited volumes of the intact specimen, at 50-microm isotropic resolution; and isolated organs, at 25-microm isotropic resolution. The three-dimensional imaging technique was applied to uricase knockout mice to demonstrate t...