University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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Folic acid

  • IUPAC Name: (2S)-2-[[4-[(2-amino-4-oxo-1H-pteridin-6-yl)methylamino]benzoyl]amino]pentanedioic acid
  • Molecular Formula: C19H19N7O6
  • CAS Registry Number: 59-30-3
  • InChI: InChI=1S/C19H19N7O6/c20-19-25-15-14(17(30)26-19)23-11(8-22-15)7-21-10-3-1-9(2-4-10)16(29)24-12(18(31)32)5-6-13(27)28/h1-4,8,12,21H,5-7H2,(H,24,29)(H,27,28)(H,31,32)(H3,20,22,25,26,30)/t12-/m0/s1
  • InChI Key: OVBPIULPVIDEAO-LBPRGKRZSA-N

@ ChemSpider@ NIST@ PubChem

Citations 4

"Adsorptive Stripping Voltammetry On Mercury-coated Carbon-fibre Ultra-micro-electrodes"
Anal. Chim. Acta 1993 Volume 273, Issue 1-2 Pages 101-109
J. Amez del Pozo, A. Costa García and P. Tuñón Blanco*

Abstract: The ultra-micro-electrodes were prepared by sealing a 2-cm length of 7.5 µm diameter carbon fiber into a 100 µL micropipette, a 0.5-mm length of the fiber being permitted to project from the micropipette tip; Hg and Cu wire were used for electrical contact. After being cleaned with chromic acid and HNO3 such a micro-electrode was used to determine mitozantrone (I) by immersion in a solution of I in 0.1 M HClO4 containing 0.1 mM Hg(II), which was electro-deposited on the electrode for 60 s at -1.2 V vs. Ag/AgCl. The potential was then held at -0.2 V for, e.g., 3 s before I was determined by phase-selective a.c. voltammetry at 75 Hz with a superimposed voltage amplitude of 25 mV and a detection angle of 90°C. Calibration graphs were rectilinear from 0.5 (detection limit) to 20 nM-I. In the determination of 5 nM-I the RSD was 5.05% (n = 10). In the determination of 10 nM-I there was little or no interference from surfactants, e.g., SDS. Procedures for the determination of I in urine and of folic acid in aqueous solution are also described. Such electrodes, which could be used for 1 to 2 months without loss in sensitivity, might be useful in flow injection analysis or LC.
Urine Water Voltammetry Electrode Electrode Interferences

"Photochemical-fluorimetric Determination Of Folic Acid In A Multicommutated Flow System"
Anal. Chim. Acta 1997 Volume 351, Issue 1-3 Pages 223-228
Rui A. S. Lapa*, JoséL. F. C. Lima, Boaventura F. Reis, João L. M. Santos and Elias A. G. Zagatto

Abstract: A flow system based on multicommutation was developed for the determination of folic acid by fluorimetry following irradiation by ultraviolet light. The photochemical reaction was carried out in a reaction coil. Insertion of time-controlled sample volumes enabled the determination of a wide range of concentrations without changing the manifold design, which makes it suitable for application to automated dissolution studies. An automated system control selects for each sample, depending on its concentration, the sampling time and therefore the most convenient sample volume. Linear calibration plots were obtained over a concentration range from 0.1 to 40.0 mg L-1 with a relative standard deviation of less than 3% and a sampling rate of about 25 samples per hour.
Fluorescence Photochemistry Multicommutation

"Flow Injection Chemiluminometric Determination Of Folic Acid In Pharmaceutical Formulations"
Anal. Sci. 1994 Volume 10, Issue 6 Pages 919-922
A. A. AL-WARTHAN

Abstract: A 5 mM Ce(IV) solution in 0.15 M H2SO4 was introduced into the flow system at 5.25 ml/min and mixed with standard solutions of folic acid (I) in 50 mM HCl. Immediately before entering the flow cell the solution was mixed with a 0.5 mM sulfite aqueous solution containing 10 µM-Rhodamine B flowing at 5.25 ml/min. The chemiluminescence of the final solution entering the coiled flow cell was measured. The calibration graph was linear from 10 nM- to 10 µM-I. The RSD (n = 10) was 0.54% for 11 µM-I. The method was applied to the determination of folic acid in pharmaceutical preparations and the results compared well with those obtained by the British Pharmacopoeia standard method.
Pharmaceutical Chemiluminescence Standard method Method comparison

"Simultaneous Determination Of Water-Soluble Vitamins In Human Urine By Fluorescence In A Flow-Injection Analysis"
J. Liq. Chromatogr. Relat. Technol. 2006 Volume 29, Issue 3 Pages 329-338
Lai-Hao Wang, Heng-Chieh Hung

Abstract: Fluorescence in flow-injection analysis is described for the simultaneous determination of thiamine, riboflavin, and folic acid. Its detection limit linearity and reproducibility were examined. The kinetic method is based on the enhancing effect of thiamine and riboflavin on the fluorescence generated by oxidizing to thiochrome with alkaline ferricyanide. Different parameters affecting this reaction were thoroughly studied. The procedure was applied to the determination of thiamine and riboflavin and folic acid in human urine samples.
Urine Fluorescence Kinetic