scholarly journals Detection and Assay of Vitamin B-2 (Riboflavin) in Alkaline Borate Buffer with UV/Visible Spectrophotometry

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Ronald Bartzatt ◽  
Tasloach Wol
Keyword(s):  
Aqueous Media ◽  
Borate Buffer ◽  
Sodium Borate ◽  
Vitamin B ◽  
Standard Curve ◽  
Uv Visible ◽  
Aqueous Conditions ◽  
Sufficient Vitamin ◽  
Sodium Borate Buffer ◽  
B Vitamin

The detection and assay of vitamin B-2 (riboflavin) was accomplished under aqueous conditions using sodium borate buffering at pH 7.52 conditions. The absorbance spectrum of riboflavin was determined at different pH values utilizing several buffers. The buffer at pH at 7.52 is followed by accurate and sensitive assay of riboflavin by spectrophotometer at 440 nm wavelength. Where indicated an origin solution (stock) was employed by dissolving sufficient vitamin to make a stock solution of 1.403×10-4 molar concentrations. Measurements of various aqueous solutions containing riboflavin were accomplished that included aqueous test samples, vitamin capsules/tablets, and water vitamin mixtures. A standard curve extended from 7.97×10-7 molar to 1.23×10-4 molar (a 154x folds spread in concentration). The equation of the line was y = 12545x (intercept at origin) with Pearson r correlation of 1.000 (R2=1.000). Concentration of riboflavin assayed ranged from 3.00×10-4 gram per liter (0.30 ppm) to 0.0463 gram per liter (46.35 ppm). The B vitamin riboflavin can be assayed by UV/VIS spectrophotometer at 440 nm in aqueous media and using sodium borate buffer at pH 7.52. The assay can reach as low as 0.30 parts per million with high levels of accuracy and sensitivity.

Decomposition of 4,4'-(Diazoamino)-bis(5-methoxy-2-methylbenezenesulfonic Acid) in Solutions ofFD&C Red No. 40

1984 ◽  
Vol 67 (4) ◽  
pp. 844-845
Author(s):  
Naomi Richfield-Fratz
Keyword(s):  
Liquid Chromatography ◽  
Aqueous Solutions ◽  
Borate Buffer ◽  
Sodium Borate ◽  
First Order ◽  
First Order Kinetics ◽  
Color Additive ◽  
Sodium Borate Buffer

Abstract 4,4'-(Diazoamino)-bis(5-methoxy-2-methylbenzenesuIfonic acid), when present as a reaction by-product in FD&C Red No. 40, is shown to decompose rapidly in aqueous solutions of the color additive. The decomposition is halted by the addition of sodium borate buffer. Quantitationly liquid chromatography shows that decomposition is nonlinear with time and follows approximate first order kinetics.

STEROID FOCUSING BY MICELLE COLLAPSE IN MICELLAR ELECTROKINETIC CHROMATOGRAPHY

2012 ◽  
Vol 57 (1) ◽  
Author(s):  
NORTHAQIFAH HASNA MOHAMED KHIR ◽  
JAFARIAH JAAFAR ◽  
MOHD BAKRI BAKAR
Keyword(s):  
Micellar Electrokinetic Chromatography ◽  
Limit Of Detection ◽  
Sodium Dodecyl ◽  
Borate Buffer ◽  
Sodium Borate ◽  
Electrokinetic Chromatography ◽  
Good Separation ◽  
Phase Zone ◽  
Sodium Borate Buffer ◽  
Buffer Condition

Preliminary studies on the separation of neutral steroids through analyte focusing by micelle collapse (AFMC) are presented to investigate its efficiency, sensitivity and limit of detection (LOD). The focusing mechanism of AFMC is based on the transport, release, and accumulation of molecules bound to micelle carriers that are made to collapse into a liquid phase zone. The sample solution of the neutral analytes (S) is prepared using sodium dodecyl sulphate (SDS) at a concentration above the critical micelle concentration (cmc) with higher conductivity than the running buffer. Normal mode–micellar electrokinetic chromatography (NM–MEKC) separation was initially performed on 100 mg/L of six neutral steroids in methanol using 20 mM SDS, 10% (v/v) methanol and sodium borate buffer (pH 9.0) with positive applied voltage of 25 kV and pressure injection of 50 mbar for 1 sec at 25°C. The same buffer condition has been applied to AFMC–MEKC, whereby the mixture of six neutral steroids was dissolved in 2 mM SDS and 250 mM sodium borate buffer which gave a conductivity ratio of 0.49. Results showed a good separation of prednisolone, prednisone, betamethasone, testosterone, 17–α–methyltestosterone, and 4–androstene–3,17–dione at 240 nm with sensitivity enhancement factors of 2.08, 1.17, 0.92, 16.9, 0.8, and 1.21 respectively. AFMC–MEKC allowed several folds improvement in sensitivity compared to NM–MEKC.

Formation of Artifactual Ammonia in Blood by Action of Alkali

1961 ◽  
Vol 7 (1) ◽  
pp. 54-69 ◽  
Author(s):  
John G Reinhold ◽  
Charles C Chung
Keyword(s):  
Diffusion Process ◽  
Borate Buffer ◽  
Sodium Borate ◽  
Blood Protein ◽  
Critical Importance ◽  
Blood Samples ◽  
Spontaneous Production ◽  
Sodium Borate Buffer ◽  
Production Of Ammonia ◽  
Standard Solutions

Abstract Data are presented that demonstrate that ammonia is formed in the course of the analysis of blood samples. The formation has been traced to the decomposition of protein by the action of alkali. The pH established during the diffusion process was of critical importance in the measurements. A technic is described by which ammonia is displaced from blood by a sodium borate buffer at a pH that avoids spontaneous production of ammonia from blood protein. The Seligson-Seligson microdiffusion apparatus is used. Instructions are given for the collection of blood samples and the preparation of reagents and standard solutions.

Thiamine (Vitamin B1)

2011 ◽  
Vol 16 (1) ◽  
pp. 12-20 ◽  
Author(s):  
Aviva Fattal-Valevski
Keyword(s):  
Cognitive Impairment ◽  
Cerebral Metabolism ◽  
Oxidant Stress ◽  
Vitamin B1 ◽  
Vitamin B ◽  
Deficient Diet ◽  
Common Cause ◽  
Korsakoff Syndrome ◽  
Reducing Substances ◽  
B Vitamin

Thiamine (vitamin B1) was the first B vitamin to have been identified. It serves as a cofactor for several enzymes involved in energy metabolism. The thiamine-dependent enzymes are important for the biosynthesis of neurotransmitters and for the production of reducing substances used in oxidant stress defenses, as well as for the synthesis of pentoses used as nucleic acid precursors. Thiamine plays a central role in cerebral metabolism. Its deficiency results in dry beriberi, a peripheral neuropathy, wet beriberi, a cardiomyopathy with edema and lactic acidosis, and Wernicke—Korsakoff syndrome, whose manifestations consist of nystagmus, ophthalmoplegia, and ataxia evolving into confusion, retrograde amnesia, cognitive impairment, and confabulation. Patients on a strict thiamine-deficient diet display a state of severe depletion within 18 days. The most common cause of thiamine deficiency in affluent countries is either alcoholism or malnutrition in nonalcoholic patients. Treatment by thiamine supplementation is beneficial for diagnostic and therapeutic purposes.

Free-base corroles: determination of deprotonation constants in non-aqueous media

2007 ◽  
Vol 11 (04) ◽  
pp. 269-276 ◽  
Author(s):  
Jing Shen ◽  
Zhongping Ou ◽  
Jianguo Shao ◽  
Michał Gałęzowski ◽  
Daniel T. Gryko ◽  
...  
Keyword(s):  
Equilibrium Constants ◽  
Aqueous Media ◽  
Free Base ◽  
Organic Base ◽  
Experimental Conditions ◽  
Spectral Changes ◽  
Base Analysis ◽  
Uv Visible ◽  
The Given

A series of free-base corroles with different electron-donating or electron-withdrawing substituents were reacted with piperidine, 4-aminopyridine, 2-methylimidazole, 2-aminopyridine or pyridine in PhCN and the UV-visible spectral changes monitored during conversion of ( Cor ) H 3 to [( Cor ) H 2]- as a function of the concentration and strength of the added organic base. Analysis of the UV-visible spectral changes as a function of the added base concentration enabled calculation of equilibrium constants ( logK ) for deprotonation of each corrole under the given experimental conditions. Relationships are examined between the experimentally measured logK values and previously published spectroscopic and structural properties of the compounds.

scholarly journals Naphthyridine derived colorimetric and fluorescent turn off sensors for Ni2+ in aqueous media

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Abida Ashraf ◽  
Muhammad Islam ◽  
Muhammad Khalid ◽  
Anthony P. Davis ◽  
Muhammad Tayyeb Ahsan ◽  
...  
Keyword(s):  
Dft Calculations ◽  
Color Change ◽  
Aqueous Media ◽  
Field Measurements ◽  
Spectral Changes ◽  
Energy Gaps ◽  
Td Dft ◽  
Distinct Color ◽  
Uv Visible ◽  
Metal Charge Transfer

AbstractHighly selective and sensitive 2,7-naphthyridine based colorimetric and fluorescence “Turn Off” chemosensors (L1-L4) for detection of Ni2+ in aqueous media are reported. The receptors (L1-L4) showed a distinct color change from yellow to red by addition of Ni2+ with spectral changes in bands at 535–550 nm. The changes are reversible and pH independent. The detection limits for Ni2+ by (L1-L4) are in the range of 0.2–0.5 µM by UV–Visible data and 0.040–0.47 µM by fluorescence data, which is lower than the permissible value of Ni2+ (1.2 µM) in drinking water defined by EPA. The binding stoichiometries of L1-L4 for Ni2+ were found to be 2:1 through Job’s plot and ESI–MS analysis. Moreover the receptors can be used to quantify Ni2+ in real water samples. Formation of test strips by the dip-stick method increases the practical applicability of the Ni2+ test for “in-the-field” measurements. DFT calculations and AIM analyses supported the experimentally determined 2:1 stoichiometries of complexation. TD-DFT calculations were performed which showed slightly decreased FMO energy gaps due to ligand–metal charge transfer (LMCT).

B-COMPLEX VITAMIN SUPPLEMENTATION OF PIG RATIONS BASED ON BARLEY GROWN ON GREY WOODED SOILS

1962 ◽  
Vol 42 (2) ◽  
pp. 183-190 ◽  
Author(s):  
B. D. Owen ◽  
A. Reddon ◽  
F. Whiting
Keyword(s):  
Nicotinic Acid ◽  
Post Partum ◽  
Pantothenic Acid ◽  
Vitamin Supplementation ◽  
Vitamin B ◽  
Growth Responses ◽  
Growing Period ◽  
Peace River ◽  
River Region ◽  
B Vitamin

Ninety-two sows and two hundred and sixteen pigs were employed in four gestation-lactation and three growing-finishing experiments to determine the adequacy of barley grown on the Grey Wooded soils of the Peace River region in northwestern Canada, as a source of riboflavin, pantothenic and nicotinic acid in swine rations. Vitamin B12 was assessed as a dietary essential in the all-plant rations. In the gestation-lactation experiments sow gains during gestation were greater in the B-vitamin supplemented lot and a trend toward heavier weaning weights of pigs was evident. Vitamin supplementation increased the level of vitamin B12 in sow’s milk collected 1 week post-partum and of both riboflavin and pantothenic acid collected 1 week and 6 weeks post-partum. Nicotinic acid content of sows’ milk was unaffected by supplementation. There was a highly significant decrease in riboflavin level in both control and supplemented lots between 1 and 6 weeks following parturition. The decrease was greatest in the unsupplemented lot.B-vitamin supplementation did not affect growing period gains or pig carcass quality in the growing-finishing experiments. However, certain significant growth responses were noted in the finishing period.The data indicate that the basal rations employed contained adequate riboflavin, pantothenic and nicotinic acid to support normal gestation, lactation and growth in Yorkshire swine.

scholarly journals Associations between B vitamin and amino acid intake, MTHFR genotype, atherogenic indices, and homocysteine levels in postmenopausal women

2020 ◽  
Vol 79 (OCE2) ◽  
Author(s):  
Agata Muzsik ◽  
Agata Chmurzynska
Keyword(s):  
Lipid Metabolism ◽  
Amino Acid ◽  
Lipid Profile ◽  
Postmenopausal Women ◽  
Folate Intake ◽  
Vitamin B ◽  
Vitamin Intake ◽  
Atherogenic Indices ◽  
Amino Acid Intake ◽  
B Vitamin

AbstractIt has been hypothesized that insufficiency of one-carbon metabolism may aggravate lipid metabolism disturbances. Lipid metabolism abnormalities and metabolic syndrome (MetS)—which is associated with abnormally high levels of triglycerides (TG) and low levels of high-density lipoproteins (HDL)—often occur in postmenopausal women. The purpose of this study was thus to determine the relationships between amino acid and B vitamin intake, MTHFR genotype, lipid profile, and atherogenic indices in postmenopausal women.131 postmenopausal women were enrolled for the study. The mean macronutrient, amino acid, and B vitamin intake was evaluated using dietary records. Lipid profile and concentrations of apolipoprotein A1 (ApoA1) and B (ApoB) in serum were measured using the colorimetric method. The total homocysteine (tHcy) and glutathione (GSH) level in plasma were measured using high-performance liquid chromatography. MTHFR genotype (rs1801133) was determined using a single tube TaqMan SNP Genotyping Assay. We calculated atherogenic indices, such as Castelli's risk index I and II (CRI-I and CRI-II), the atherogenic coefficient (AC), and the TG/HDL ratio.No association was found between MetS and tHcy or GSH concentrations. MTHFR genotype and folate intake also did not affect tHcy, GSH, lipid profile, or atherogenic indices. Subjects with tHcy levels over the median had lower total protein intake, lower animal protein/plant protein ratio, lower protein/carbohydrates ratio, and higher amino acid intake (methionine, lysine, arginine, glycine, and tryptophan) than did subjects with lower tHcy levels. Women who failed to meet their vitamin B12 intake needs had almost 40% higher levels of tHcy than women who did met those needs.MTHFR genotype, folate intake, and tHcy levels in plasma are not associated with lipid metabolism in postmenopausal women. tHcy levels may depend on the intake of vitamin B12, and of protein or particular amino acids.The project was financed by the National Science Centre, Poland (grant number 2015/17/N/NZ9/04133).

scholarly journals Highly stable noble metal nanoparticles dispersible in biocompatible solvents: synthesis of cationic phosphonium gold nanoparticles in water and DMSO

2016 ◽  
Vol 186 ◽  
pp. 77-93 ◽  
Author(s):  
Yon Ju-Nam ◽  
Wanisa Abdussalam-Mohammed ◽  
Jesus J. Ojeda
Keyword(s):  
Gold Nanoparticles ◽  
Drug Carrier ◽  
Aqueous Media ◽  
Noble Metal Nanoparticles ◽  
Great Opportunity ◽  
Thiolate Ligands ◽  
New Family ◽  
Uv Visible ◽  
Potential Use

In this work, we report the synthesis of novel cationic phosphonium gold nanoparticles dispersible in water and dimethyl sulfoxide (DMSO) for their potential use in biomedical applications. All the cationic-functionalising ligands currently reported in the literature are ammonium-based species. Here, the synthesis and characterisation of an alternative system, based on phosphonioalkylthiosulfate zwitterions and phosphonioalkylthioacetate were carried out. We have also demonstrated that our phosphonioalkylthiosulfate zwitterions readily disproportionate into phosphonioalkylthiolates in situ during the synthesis of gold nanoparticles produced by the borohydride reduction of gold(iii) salts. The synthesis of the cationic gold nanoparticles using these phosphonium ligands was carried out in water and DMSO. UV-visible spectroscopic and TEM studies have shown that the phosphonioalkylthiolates bind to the surface of gold nanoparticles which are typically around 10 nm in diameter. The resulting cationic-functionalised gold nanoparticles are dispersible in aqueous media and in DMSO, which is the only organic solvent approved by the U.S. Food and Drug Administration (FDA) for drug carrier tests. This indicates their potential future use in biological applications. This work shows the synthesis of a new family of phosphonium-based ligands, which behave as cationic masked thiolate ligands in the functionalisation of gold nanoparticles. These highly stable colloidal cationic phosphonium gold nanoparticles dispersed in water and DMSO can offer a great opportunity for the design of novel biorecognition and drug delivery systems.

An immobilized symmetrical bis-(NHC) palladium complex as a highly efficient and recyclable Suzuki–Miyaura catalyst in aerobic aqueous media

2017 ◽  
Vol 46 (2) ◽  
pp. 539-546 ◽  
Author(s):  
Tahshina Begum ◽  
Manoj Mondal ◽  
Manash Protim Borpuzari ◽  
Rahul Kar ◽  
Golap Kalita ◽  
...  
Keyword(s):  
Palladium Complex ◽  
Aqueous Media ◽  
Coupling Reaction ◽  
Cross Coupling ◽  
Recyclable Catalyst ◽  
Highly Efficient ◽  
Cross Coupling Reaction ◽  
Aqueous Conditions

A novel palladium-silica complex was prepared and characterized. This complex is a highly efficient and easily recyclable catalyst for Suzuki–Miyaura cross-coupling reaction under mild aqueous conditions, and can be reused efficiently up to 6 consecutive runs.

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