Isatin (indole-2,3-dione) in urine and tissues. Detection and determination by gas chromatography-mass spectrometry.
A simple procedure based upon capillary column gas chromatography-mass spectrometry (GC-MS) is described for the detection and determination of isatin (indole-2,3-dione) in body fluids and tissues. After addition of 5-methylisatin as internal standard to urine or tissue homogenates, organic extracts are dried and derivatized successively with hydroxylamine hydrochloride and the reagent N-tert.-butyldimethylsilyl-N-methyltrifluoroacetamide (MTBSTFA). The tert.-butyldimethylsilyl derivatives obtained show good GC-MS properties and allow quantification by selected-ion monitoring of m/z 333 (isatin) and m/z 347 (internal standard). Adult and newborn human urine output values lie in the ranges 0.4-3.2 mg/mmol of creatinine (5-30 mg per 24 h) and 0.002-0.518 mg/mmol of creatinine, respectively. There is a discontinuous regional distribution in rat tissues. The GC-MS properties of a number of derivatives formed by successive reaction of isatin with hydroxylamine hydrochloride (or methoxyaminehydrochloride or ethoxyamine hydrochloride) and MTBSTFA, bis(trimethylsiyl)trifluoroacetamide, pentafluoropropionic anhydride or pentafluorobenzyl bromide are also described.
Halket
J M
JM
Department of Chemical Pathology, Royal Postgraduate Medical School, Queen Charlotte's and Chelsea Hospital, London, U.K.
Watkins
P J
PJ
Przyborowska
A
A
Goodwin
B L
BL
Clow
A
A
Glover
V
V
Sandler
M
M
D000081:Acetamides; D000328:Adult; D000818:Animals; D001923:Brain Chemistry / Q000187:drug effects; D005461:Fluorine / Q000032:analysis; D005463:Fluoroacetates; D005464:Fluorobenzenes; D005466:Fluorocarbons; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D007510:Isatin / Q000032:analysis* / Q000652:urine; D017646:Organosilicon Compounds; D010091:Oximes / Q000378:metabolism; D051381:Rats; D014297:Trimethylsilyl Compounds
D000081:Acetamides; D005463:Fluoroacetates; D005464:Fluorobenzenes; D005466:Fluorocarbons; D017646:Organosilicon Compounds; D010091:Oximes; D014297:Trimethylsilyl Compounds; C068048:pentafluoropropionic anhydride; C025063:pentafluorobenzyl bromide; D005461:Fluorine; C059151:N-methyl-N-(tert-butyldimethylsilyl)trifluoroacetamide; D007510:Isatin