Observations on the Zak Cholesterol Reaction: Glacial Acetic Acid Purity, a More Sensitive Absorbance Peak, and Bromide Enhancement

1962 ◽  
Vol 8 (3) ◽  
pp. 296-301 ◽  
Author(s):  
Robert E Bowman ◽  
Richard C Wolf
Keyword(s):  
Acetic Acid ◽  
Glacial Acetic Acid ◽  
Enhancement Effect ◽  
Optimum Conditions ◽  
Absorbance Spectrum ◽  
Iodide Ions ◽  
Color Reagent ◽  
Absorbance Peak

Abstract An examination of the absorbance spectrum of the Zak cholesterol reaction, made with two brands of commercially available reagent-grade glacial acetic acid, showed not only the expected peak at 560 mµ, but an additional, higher peak at about 490 mµ. A specially purified glacial acetic acid did not show this 490 mµ peak. Conversely, increasing the ratio of color reagent to glacial acetic acid from 0.8 to 1.2 (v/v) greatly increased the height of the absorbance peak at 480 mµ and eliminated the 560 mµ peak. Under optimum conditions of time and color-reagent concentrations, the 480 mµ peak affords approximately double the sensitivity for cholesterol as compared to the 560 mµ peak. Finally, it was observed that the reported interference of bromide and iodide ions in the Zak reaction results almost entirely from an enhancement effect on the color by the cholesterol itself, and that the addition of about 100 µg. NaBr per milliliter of glacial acetic acid prior to reaction produced the full enhancement of 50 per cent greater color, and virtually eliminated interference at 560 mµ from additional amounts of bromide or iodide salts.

A Rapid and Specific Ultramicro Method for Total Serum Cholesterol

1962 ◽  
Vol 8 (3) ◽  
pp. 302-309 ◽  
Author(s):  
Robert E Bowman ◽  
Richard C Wolf
Keyword(s):  
Acetic Acid ◽  
Satisfactory Agreement ◽  
Glacial Acetic Acid ◽  
Total Serum ◽  
Total Serum Cholesterol ◽  
High Cholesterol ◽  
Absorbance Spectrum ◽  
Human Sera ◽  
Color Reagent ◽  
Acid Reaction

Abstract A modification of the Zak cholesterol reaction is described in which ethanol is substituted for glacial acetic acid. This modification avoids the hazard of purifying glacial acetic acid and also increases the specificity of the reaction by eliminating interference from bromide or iodide salts. The ethanolic reaction has the absorbance spectrum, sensitivity, and stability of the usual acetic acid reaction. A rapid ultramicro method has been developed based on this ethanolic reaction. A 0.01- to 0.05-ml. sample of serum is extracted with 2.5 ml. of ethanol, and a 2.0-ml. aliquot of this extract is reacted directly with 2.0 ml. of a Zak color reagent. Cholesterol concentrations as determined by this procedure and by the Sperry-Webb method showed satisfactory agreement for monkey and human sera, including normal, hemolyzed, high cholesterol, and severely lipemic or jaundiced sera..

scholarly journals PEMBUATAN SELULOSA ASETAT DARI α -SELULOSA TANDAN KOSONG KELAPA SAWIT

2013 ◽  
Vol 2 (3) ◽  
pp. 33-39 ◽  
Author(s):  
M Roganda L Lumban Gaol ◽  
Roganda Sitorus ◽  
Yanthi S ◽  
Indra Surya ◽  
Renita Manurung
Keyword(s):  
Acetic Acid ◽  
Oil Palm ◽  
Sodium Acetate ◽  
Glacial Acetic Acid ◽  
Acid Anhydride ◽  
Ftir Analysis ◽  
Optimum Conditions ◽  
Empty Fruit Bunches ◽  
Last Stage ◽  
Cellulose Materials

Utilization of empty fruit bunches of oil palm in Indonesia is still very low, so it should be developed further. One of them by researching the manufacture of cellulose acetate from oil palm empty fruit bunches. The process used in this study is the cellanase with α-cellulose materials. Stages reaction is activation, acetylation, hydrolysis, neutralization and drying. Activation in thethree-neck flask with the addition of 50 ml of glacial acetic acid and stirredfor 3 hour,then added 15 ml of acetic acid anhydride as acetylation agent. Acetylation performed with the variation of time, 2, 2.5, 3, 3.5 hours.  In the hydrolysis step, add 2 ml of water and5 ml of glacial acetic acid. The reaction lasted for 30 minutes, then added 1 g of sodium acetate for neutralization, neutralization lasts for 5 minutes.  Then do the washing up to the smell of acetic acid is lost, and the last stage is the drying is done with a temperature below 50 oC.  The resulting products are then analyzed the degree of substitution, melting point, and then carried out FTIR analysis.  The results obtained when the optimum conditions for the acetylation reaction is 2.5 - 3 hours.

scholarly journals Study on the Factors Influencing the Extraction of Chenodeoxycholic Acid from Duck Bile Paste by Calcium Salt Method

2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
Xiangzheng Hu ◽  
Na Feng ◽  
Jiaqi Zhang
Keyword(s):  
Hydrogen Peroxide ◽  
Acetic Acid ◽  
Calcium Chloride ◽  
Methyl Alcohol ◽  
Chenodeoxycholic Acid ◽  
Glacial Acetic Acid ◽  
Calcium Salt ◽  
Orthogonal Experimental Design ◽  
Optimum Conditions ◽  
Extraction Technology

New extraction technology of chenodeoxycholic acid from duck bile paste by calcium salt was investigated. The optimum conditions of extraction were determined by orthogonal experimental design. The results indicated that influencing factors on the extraction efficiency of chenodeoxycholic acid were as follows: hydrogen peroxide, methyl alcohol, glacial acetic acid, and calcium chloride. The optimum extracting conditions of chenodeoxycholic acid were 1000 mL amount of methyl alcohol, 50 mL amount of hydrogen peroxide, 500 mL amount of 20% calcium chloride, and 600 mL amount of 60% glacial acetic acid for a quantity of duck paste. The yield of chenodeoxycholic acid was 30%.

Synthesis and Caracterization of some New 1H-3-aryl-7-etoxycarbonyl-6-methyl-pyrazolo[5,1-c][1,2,4]triazoles

2008 ◽  
Vol 59 (1) ◽  
pp. 41-44
Author(s):  
Maria-Daniela Sofei ◽  
Maria Ilici ◽  
Valentin Badea ◽  
Carol Csunderlik ◽  
Vasile-Nicolae Bercean
Keyword(s):  
Mass Spectrometry ◽  
Acetic Acid ◽  
Nmr Spectroscopy ◽  
Sodium Acetate ◽  
Glacial Acetic Acid ◽  
Ir And Nmr Spectroscopy

The synthesis of 1H-3-aryl-7-ethoxycarbonyl-6-methyl-pyrazolo[5,1-c][1,2,4]triazoles (2) was carried out by cyclization of 1H-5-arylidenehydrazino-4-ethoxycarbonyl-3-methyl-pyrazoles (1) in the presence of bromine using glacial acetic acid as solvent and sodium acetate as base. The new nine obtained compounds were characterized by IR and NMR spectroscopy and mass spectrometry.

Coordination state of cobalt(II) ions in solution and on a sulphonated organic polymer

1979 ◽  
Vol 44 (8) ◽  
pp. 2330-2337 ◽  
Author(s):  
Jindřiška Maternová ◽  
Anastas A. Andreev ◽  
Dimitrii M. Shopov ◽  
Karel Setínek
Keyword(s):  
Acetic Acid ◽  
Coordination Sphere ◽  
Glacial Acetic Acid ◽  
Organic Polymer ◽  
Octahedral Complex ◽  
Coordination State ◽  
Tetrahedral Symmetry ◽  
Liquid Acid ◽  
Homogeneous Phase ◽  
Bromide Ion

It was found spectroscopically that cobalt(II) acetate dissolved in glacial acetic acid forms the octahedral complex [Co(OAc)2(HOAc)4] which in the presence of bromide ions gives the octahedral [Co(OAc)Br(HOAc)4] and tetrahedral bromo(acetate)cobalt(II) complexes with the higher number of Br- ions. When attached to an organic polymer cobalt(II) ions are bonded in the form of octahedral [Co(H2O)6]2+ cations which form with acetic acid similar complexes as in homogeneous phase and are able to coordinate one bromide ion. Drying the copolymer possessing octahedral hexaaquocobalt(II) cations leads to tetrahedral aquocomplexes which are solvated by gaseous acetic acid and converted into the acetate complexes with the liquid acid. The latter contain the acid in the inner coordination sphere and have tetrahedral symmetry.

scholarly journals Nitration of Jharia basin coals, India: a study of structural modifications by XRD and FTIR techniques

2021 ◽  
Author(s):  
Prabal Boral ◽  
Atul K. Varma ◽  
Sudip Maity
Keyword(s):  
Acetic Acid ◽  
Nitric Acid ◽  
Linear Relationship ◽  
Glacial Acetic Acid ◽  
Vitrinite Reflectance ◽  
Aqueous Media ◽  
Interlayer Spacing ◽  
Acetic Acid Medium ◽  
X Ray ◽  
The Media

AbstractFour coal samples from Jharia basin, India are treated with nitric acid in glacial acetic acid and aqueous media to find out the chemical, petrographic and spatial structure of the organic mass by X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) techniques. X-ray parameters of coal like interlayer spacing (d002), crystallite size (Lc), aroamticity (fa), average number of aromatic layers (Nc), and coal rank (I26/I20) have been determined using profile-fitting software. Considerable variation is observed in treated coals in comparison to the demineralized coals. The d002 values of treated coals have increased in both the media showing increase in disordering of organic moieties. A linear relationship has been observed between d002 values with the volatile matter of the coals. Similarly, the d002 values show linear relationship with Cdmf contents for demineralized as well as for the treated coals in both the media. The Lc and Nc values have decreased in treated coals corresponding to demineralized coals. The present study shows that nitration in both the media is capable of removing the aliphatic side chains from the coals and aromaticity (fa) increases with increase in rank and shows a linear relationship with the vitrinite reflectance. The corresponding I26/I20 values are least for treated coals in glacial acetic acid medium followed by raw and then to treated coals in aqueous medium. FTIR studies show that coal arenes of the raw coals are converted into nitro-arenes in structurally modified coals (SMCs) in both the media, the corresponding bands at 1550–1490 and 1355–1315 cm−1 respectively. FTIR study confirms that nitration is the predominant phenomenon, though, oxidation and nitration phenomena takes place simultaneously during treatment with nitric acid to form SMCs. In comparison to raw coals, the SMCs show higher aromaticity and may be easily converted to coal derived products like activated carbon and specialty carbon materials.

HSCCC Separation of Three Main Compounds from the Crude Extract of Dracocephalum Tanguticum by Using Dimethyl Sulfoxide as Cosolvent

2020 ◽  
Author(s):  
Xue Yang ◽  
Yongling Liu ◽  
Tao Chen ◽  
Nana Wang ◽  
Hongmei Li ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Ethyl Acetate ◽  
Dimethyl Sulfoxide ◽  
Efficient Method ◽  
Crude Extract ◽  
High Speed ◽  
Glacial Acetic Acid ◽  
Butyl Alcohol ◽  
Preparative Hplc ◽  
Counter Current

Abstract Separation of natural compounds directly from the crude extract is a challenging work for traditional column chromatography. In the present study, an efficient method for separation of three main compounds from the crude extract of Dracocephalum tanguticum has been successfully established by high-speed counter-current chromatography (HSCCC). The crude extract was directly introduced into HSCCC by using dimethyl sulfoxide as cosolvent. Ethyl acetate/n-butyl alcohol/0.3% glacial acetic acid (4: 1: 5, v/v) system was used and three target compounds with purity higher than 80% were obtained. Preparative HPLC was used for further purification and three target compounds with purity higher than 98% were obtained. The compounds were identified as chlorogenic acid, pedaliin and pedaliin-6″-acetate.

Kinetics of the acid-catalyzed isomerization of phenylbutenes in glacial acetic acid

1972 ◽  
Vol 94 (4) ◽  
pp. 1247-1249 ◽  
Author(s):  
R. S. Schwartz ◽  
H. Yokokawa ◽  
E. W. Graham
Keyword(s):  
Acetic Acid ◽  
Glacial Acetic Acid ◽  
Acid Catalyzed ◽  
Kinetics Of
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