85-87-0Relevant articles and documents
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Bruice,Topping
, p. 2448 (1962)
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Pyridoxamine-5-phosphate enzyme-linked immune mass spectrometric assay substrate for linear absolute quantification of alkaline phosphatase to the yoctomole range applied to prostate specific antigen
Florentinus-Mefailoski, Angelique,Marshall, John G.
, p. 10684 - 10691 (2014)
There is a need to measure proteins that are present in concentrations below the detection limits of existing colorimetric approaches with enzyme-linked immunoabsorbent assays (ELISA). The powerful enzyme alkaline phosphatase conjugated to the highly specific bacterial protein streptavidin binds to biotinylated macromolecules like proteins, antibodies, or other ligands and receptors with a high affinity. The binding of the biotinylated detection antibody, with resulting amplification of the signal by the catalytic production of reporter molecules, is key to the sensitivity of ELISA. The specificity and amplification of the signal by the enzyme alkaline phosphatase in ELISA together with the sensitivity of liquid chromatography electrospray ionization and mass spectrometry (LC-ESI-MS) to detect femtomole to picomole amounts of reporter molecules results in an ultrasensitive enzyme-linked immune mass spectrometric assay (ELIMSA). The novel ELIMSA substrate pyridoxamine-5-phosphate (PA5P) is cleaved by the enzyme alkaline phosphatase to yield the basic and hydrophilic product pyridoxamine (PA) that elutes rapidly with symmetrical peaks and a flat baseline. Pyridoxamine (PA) and 13C PA were both observed to show a linear relationship between log ion intensity and quantity from picomole to femtomole amounts by liquid chromatography-electrospray ionization and mass spectrometry. Four independent methods, (i) internal 13C isotope PA dilution curves, (ii) internal 13C isotope one-point calibration, (iii) external PA standard curve, and (iv) external 13C PA standard curve, all agreed within 1 digit in the same order of magnitude on the linear quantification of PA. Hence, a mass spectrometer can be used to robustly detect 526 ymol of the alkaline phosphatase streptavidin probe and accurately quantify zeptomole amounts of PSA against log linear absolute standard by micro electrospray on a simple ion trap.
Kinetic and mechanism of reactions of L-α-glutamic acid and L-Glutamine with pyridoxal
Pishchugin,Tuleberdiev
, p. 1362 - 1366 (2014/10/15)
The kinetics and mechanisms of condensation of pyridoxal with L-α-glutamic acid and L-glutamine were studied by UV spectroscopy and polarimetry. L-α-Glutamic acid reacts with pyridoxal to form a Schiff base whose subsequent hydrolysis gives rise to pyridoxamine and α-ketoglutaric acid. The reaction of Lglutamine with pyridoxal involves the Γ-NH 2 group and affords a Schiff base whose subsequent hydrolysis gives rise to pyridoxamine and L-α-glutamic acid.
SUBSTITUTED PYRIDOXINE-LACTAM CARBOXYLATE SALTS
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Page/Page column 11-12, (2011/12/13)
The present invention provides salt adducts comprising at least one positively charged moiety being a pyridoxine or a derivative thereof and at least one carboxylated 5- to 7-membered lactam ring, optionally additionally substituted, methods of their preparation, and pharmaceutical compositions and medicaments comprising them. Salt adducts of the invention and compositions comprising them may be used to in the treatment of diseases or disorders associated with or inflicted by alcohol consumption.
