isoriboflavin

i·so·ri·bo·fla·vin

(ī'sō-rī'bō-flā'vin),
8-Demethyl-6-methylriboflavin; a riboflavin antimetabolite, differing from riboflavin in that the methyl groups on the isoalloxazine nucleus are in the 6,7 positions rather than the 7,8.
References in periodicals archive ?
Liquid-chromatographic measurement of riboflavin in serum and urine with isoriboflavin as internal standard.
Briefly, 50 [micro]L of isoriboflavin (internal standard) was added to 300 [micro]L of plasma and calibrators.
We appreciate the donation of the isoriboflavin internal standard by Dr.
Briefly, a 40-[micro]L plasma sample was mixed with 400 [micro]L of trichloroacetic acid (100 g/L) containing 15 nmol/L isoriboflavin (internal standard), and 330 [micro]L of the supernatant was neutralized by the addition of 108 [micro]L of [K.
Trichloroacetic acid (75 [micro]L of a 100 g/L solution) containing 15 nmol/L isoriboflavin was added to the samples, and 75 [micro]L of the supernatant was neutralized by the addition of 24 [micro]L of 2 mol/L [K.
Plasma samples (500 [micro]L) were mixed with 1500 [micro]L of ice-cold 100 g/L TCA containing 15 nmol/L isoriboflavin, which served as an internal standard.
Isoriboflavin served as the reference calibrator for riboflavin, FMN, and FAD, and riboflavin was used as the reference calibrator for isoriboflavin.
To study the stability of the internal standard in TCA used for plasma protein precipitation, we studied aliquots of 100 g/L TCA containing 150 nmol/L isoriboflavin incubated for 1, 2, 4, 7, and 14 days.
We investigated the stability of the vitamers and the internal standard in TCA-treated plasma before neutralization by adding 500 nmol/L riboflavin, FMN, FAD, or isoriboflavin to the samples.