Hamano T, Mitsuhashi Y, Aoki N, Yamamoto S, Shibata M, Ito Y, Oji Y, Lian W F
Public Health Research Institute of Kobe City, Japan.
Analyst. 1992 Jun;117(6):1033-5. doi: 10.1039/an9921701033.
A sensitive spectrophotometric method for the determination of choline in liquor is described. The method involves the conversion of choline into formaldehyde by sequential enzymic reactions (choline oxidase and catalase), followed by the formation of a chromophore with 4-aminopent-3-en-2-one. The calibration graph was linear in the range 0.4-15 micrograms cm-3 of choline. The relative standard deviation at 5 micrograms cm-3 of choline was 1.3%. There was no interference from most of the common ingredients of liquor. More than 95% of choline added at two levels was recovered from real samples. The method is simple, and the detection limit was 2 micrograms g-1 when 5 g of sample were assayed.
