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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Riboflavine

  • IUPAC Name: 7,8-dimethyl-10-[(2S,3S,4R)-2,3,4,5-tetrahydroxypentyl]benzo[g]pteridine-2,4-dione
  • Molecular Formula: C17H20N4O6
  • CAS Registry Number: 83-88-5
  • InChI: InChI=1S/C17H20N4O6/c1-7-3-9-10(4-8(7)2)21(5-11(23)14(25)12(24)6-22)15-13(18-9)16(26)20-17(27)19-15/h3-4,11-12,14,22-25H,5-6H2,1-2H3,(H,20,26,27)/t11-,12+,14-/m1/s1
  • InChI Key: AUNGANRZJHBGPY-SCRDCRAPSA-N

@ ChemSpider@ NIST@ PubChem

Citations 7

"Cyclodextrin-based Optosensor For The Determination Of Riboflavin In Pharmaceutical Preparations"
Analyst 1996 Volume 121, Issue 8 Pages 1119-1122
Zhilong Gong and Zhujun Zhang

Abstract: Tablets were dissolved in H2O; a portion was mixed with 5 mL 0.1 M NaH2PO4/0.1 M Na2HPO4 buffer of pH 6.5 (buffer A) and the mixture was diluted to 25 mL with water. A portion (2 ml) of the resulting solution was injected into a carrier stream of buffer A at a flow rate of 2 ml/min and passed through a 25 µL flow-through cell containing β-cyclodextrin immobilized on to silica gel. The fluorescence intensity of the adsorbed riboflavin/β-cyclodextrin complex was measured at 521 nm (excitation at 468 nm). The calibration graph was linear from 0.2-20 µM-riboflavin; the detection limit was 9 ng/ml. RSD was 1% (n = 7) at the 0.05 µg/ml riboflavin level.
Pharmaceutical Fluorescence Sensor Silica gel Immobilized reagent

"Study On Cobalt-PTFE Composite-plated Electrode And Its Electrochemical Properties"
Microchem. J. 1996 Volume 53, Issue 4 Pages 385-394
Hongding Xu, Mingzhu Zou, Qinhua Ru and Yunjing Luo

Abstract: A Ni disc electrode and a Co plate (0.196 cm2) were placed in an electroplating bath of pH 4-4.2 and 62±1°C. For the Co layer deposition, the bath contained 10.8 g CuSO4/NaCl/boric acid (10:1:1) in 40 mL water at 40 mA/cm2 and 9°C. For the Co-PTFE layer, the bath was 9.525 g CuSO4/NaCl/boric acid (3:10:1) in 30 mL water at 30 mA/cm2 and 1.5 C. The electroplating was carried out using a PAR173/179 potentiostat-coulometer. The resulting electrode surface was characterized by XPS and scanning electron microscopy. The chronoamperometric responses of this electrode to alcohols were studied. The electrode was also used in an FIA system with Ag and Pt wire reference and auxiliary electrodes, respectively. The responses to vitamins, amino-acids and monosaccharides were studied. The method was also applied to drug tablet analysis. The surfaces of the composite-plated electrode were smooth and uniform with PTFE particles embedded in the plated layer. The linear calibration graphs for fatty alcohols are given; detection limits were 1-10 mM. Calibration graphs were linear for the several biochemical compounds tested (ranges given); detection limits were from 1 µM-0.1 mM; RSD were 0.12-1.78%. Recoveries were from 95-105% vitamin B2 (riboflavine) in tablets.
Pharmaceutical Potentiometry Electrode Apparatus

"Highly Sensitive And Selective Determination Of Riboflavine By Flow Injection Analysis Using Parallel Dual-cylinder Micro-electrodes"
J. Electroanal. Chem. 1994 Volume 375, Issue 1-2 Pages 185-192
Wenfeng Peng, Huimei Li and Erkang Wang*

Abstract: Crushed multivitamin tablets were dissolved in 0.02 M acetic acid, and the solution was passed through a glass filter (5-15 µm), diluted to 100 mL with 0.1 M NaHSO3, further diluted tenfold with 0.1 M NaHSO3 and injected (10 µL) into a carrier stream of deoxygenated 0.1 M NaHSO3 (1 ml/min). A diagram of the wall-jet/parallel dual-cylinder micro-electrode cell is presented, and its construction is described (cf. Ibid., 1993, 347, 1). The two electrodes were maintained at -0.4 and 0 V vs. SCE, respectively, so that the current density for the oxidation of the reduced riboflavine was enhanced by 'redox recycling' (cf. Weber and Purdy, Anal. Chem., 1982, 54, 1757). The peak current at 0 V varied linearly up to 70 ng of riboflavine, and the detection limit was 35 pg. For 3.5 and 35 ng of riboflavine, the RSD (n = 10) were 2.8 and 1.7%, respectively. There was little interference; pyridoxine was reduced irreversibly at -0.4 V, and a tenfold excess did not interfere.
Pharmaceutical Electrode Electrode Amperometry Interferences Dual detection

"Comments On The Standard Fluorometric Determination Of Riboflavin In Foods And Biological Tissues"
Food Chem. 1992 Volume 43, Issue 1 Pages 79-82
L. F. Russell* and Joseph T. Vanderslice

Abstract: The vitamin B-2 content of foods has historically been determined as total riboflavin (TRF), and the most common method of TRF analysis has been the AOAC standard fluorometric procedure. A modification of this method to permit the use of flow injection analysis (FIA) is reported here. a number of foods were analyzed and the results generally agreed with the published values. However, the standard method was not found to be universally suitable for all types of samples.
Food Biological tissue Fluorescence Method comparison Standard method

"Simultaneous Determination Of Pyridoxine, Riboflavine And Thiamine In Fortified Cereal Products By High Performance Liquid Chromatography"
J. Agric. Food Chem. 1984 Volume 32, Issue 6 Pages 1326-1331
Randy L. Wehling and David L. Wetzel

Abstract: Samples were extracted with 0.1N-H2SO4 and the extracts were incubated with Clarase fungal amylase preparation in aqueous Na acetate at 55°C for 1 h. After centrifugation, the supernatant solution was filtered and analyzed by HPLC on a column (25 cm x 4.6 mm) of µBondapak C18 with a mobile phase (1 mL min-1) of methanol - water - acetic acid (30:69:1) containing 5 mM Na hexanesulfonate. Pyridoxine(I) and riboflavine(II) were determined by fluorimetric detection at 418 nm (excitation at 288 nm). Thiamine(III) was determined by post-column derivatization with alkaline Fe(CN)63- solution and detection at 460 nm (excitation at 360 nm). The limit of detection was 2 µg g-1 for I and <1 µg g-1 for II and III. The coefficient of variation obtained were 1.66, 1.51 and 2.06% for I, II and III, respectively. Good correlation (r = 0.998) was obtained with a wet-chemical fluorescence procedure, but the HPLC method was more accurate for samples containing sucrose.
Breakfast HPLC Fluorescence Post-column derivatization

"Flow Injection Analysis - Spectrophotometric Determination Of Vitamins B1 And B2 In Multi-formulation Vitamin Preparations"
Yaowu Fenxi Zazhi 1996 Volume 16, Issue 3 Pages 184-186
Yang, J.M.;Chang, H.

Abstract: Powdered sample, containing 4 mg vitamin B1 (thiamine; I), was stirred with 12 mL 0.1 M HCl for 20 min to dissolve and then shaken with 6 mL diethyl ether for 1 min; the aqueous layer was collected and diluted to 50 mL with water. A portion (10 ml) of the solution was treated with 5% KMnO4 to pink then with 10% NaNO2 to discharge color before dilution with water to 25 mL. A 140 µL portion of the solution was injected into a a carrier stream of water (0.94 ml/min) of a flow injection analyzer. (schematic shown) and mixed with reagent streams of 3.1 mM p-aminobenzenesulfonic acid diazo salt (0.5 ml/min) and 0.5 M NaOH/0.34 M Na2CO3 (0.73 ml/min) in a reactor (158 cm x 0.7 mm i.d.) and the colored product of I formed was detected at 520 nm. For the determination of vitamin B2 (riboflavine; II), the sample was injected in a similar manner but with water being used in place of the reagent streams and detection was at 440 nm. Calibration graphs were linear up to 100 and 80 µg/ml, respectively, for I and II. Recoveries were 95-101%. Results were comparable with those obtained by fluorescence spectrophotometry and LC. No interference from excipients was observed.
Pharmaceutical Spectrophotometry Interferences

"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