TLC Separation and Spectrophotometric Determination of 2-Aminoanthraquinone in D&C Blue No. 9

1969 ◽  
Vol 52 (4) ◽  
pp. 831-832
Author(s):  
Sandra J Bell
Keyword(s):  
Acetic Acid ◽  
Thin Layer ◽  
Spectrophotometric Determination ◽  
Diethyl Ether ◽  
Thin Layer Plate ◽  
Color Additive ◽  
Tlc Separation

Abstract Batches of 3,3’-dichloroindanthrene meeting the specifications set forth in the Color Additive Regulations are certifiable as D&C Blue No. 9. One of the specifications requires that D&C Blue No. 9 contain no more than 0.2% 2-aminoanthraquinone. In the method described, 2-aminoanthraquinone is extracted from D&C Blue No. 9 with dimethylsulfoxide, together with several other impurities. This solution is spotted onto a thin layer plate and developed with diethyl ether. After removal from t he plate, the 2-aminoanthraquinone is extracted into acetic acid and the amount is determined spectrophotometrically. Recoveries of 0.1, 0.2, and 0.5% of added intermediate ranged from 86 to 96%.

Notizen: Improved 2,4-Dinitrophenylhydrazine, Thin Layer Chromatography Methods for the Determination of Micro- and Macroamounts of Ascorbic Acid

1974 ◽  
Vol 29 (11-12) ◽  
pp. 777-780 ◽  
Author(s):  
A. Navon ◽  
H. Z. Levinson
Keyword(s):  
Acetic Acid ◽  
Vitamin C ◽  
Thin Layer ◽  
Condensation Reaction ◽  
Dehydroascorbic Acid ◽  
Previous Method ◽  
Aqueous Acetic Acid ◽  
Tlc Plates ◽  
Layer Chromatography

Microamounts of vitamin C could be readily determined in 20 μl-samples using the 2,4-dinitrophenylhydrazine method together with separation by thin layer chromato­graphy. The condensation reaction was carried out for 5 min at 100 °C on a glass fibre disc. Purification of vitamin C hydrazones was accomplished by repeated separation on TLC plates. An aqueous solution of 65% acetic acid was em­ployed to dissolve the vitamin C hydrazones, providing maxi­mal absorbance at 500 nm. The minimum amount detectable by this method is 0.4 μg of dehydroascorbic acid. The macrodetermination of vitamin C was improved by simpli­fying a previous method and employing 65% aqueous acetic acid as a solvent for the hydrazones.

Thin Layer Densitometric Determination of Rotenone and Deguelin

1969 ◽  
Vol 52 (1) ◽  
pp. 182-187
Author(s):  
Norman E Delfel ◽  
William H Tallent
Keyword(s):  
Acetic Acid ◽  
Standard Deviation ◽  
Nitric Acid ◽  
Thin Layer ◽  
Solvent System ◽  
Ammonia Vapor ◽  
Acid Vapor ◽  
Tephrosia Vogelii ◽  
Infrared Methods

Abstract Rutenone and deguelin are separated by chromatography on silver nitrate-impregnated silica gel G with chloroform acetone: acetic acid (196:3:1) solvent system. Glass plates, 20 × 20 cm, are coated with a special spreader producing a 0.25 mm layer and a 1.00 mm band at the upper end. Since additional solvent is required to saturate the thicker band, such plates give resolutions comparable to plates twice as long. Developed plates are treated with nitric acid vapor, then ammonia vapor, to produce dark spots for the rotenoids. Plates are scanned with a commercial densitometer, and the quantity of rotenoids is calculated from peak area in the resultant curve. Kecoveries of rotenone and deguelin added to extracts of Tephrosia vogelii, Lonchocarpus nicou, and Derris elliptica averaged 104.1 and 99.4%, respectively. The standard deviation of the method applied to plant extracts was 7.9% for rotenone and 8.3% for deguelin. The amounts of rotenone in the L. nicou samples were comparable to those determined by the AOAC crystallization and infrared methods.

Extraction and Spectrophotometry Determination of Benzthiazide, Hydrochlorothiazide, and Hydroflumethiazide in Pharmaceuticals

1970 ◽  
Vol 53 (3) ◽  
pp. 582-584
Author(s):  
F Raymond Fazzari
Keyword(s):  
Acetic Acid ◽  
Spectrophotometric Determination ◽  
Organic Phase ◽  
Active Ingredient ◽  
Separation Techniques

Abstract A method has been developed for the determination of benzthiazide, hydrochlorothiazide, and hydroflumethiazide in pharmaceuticals. The procedure is rapid and specific and employs established separation techniques. The active ingredient is eluted from a basic Celite column with an acetic acid-ether solvent and extracted from the organic phase into NaOH for the spectrophotometric determination.

Spectrophotometric Determination of Aminacrine Hydrochloride in Creams, Jellies, and Suppositories: Interlaboratory Study

1987 ◽  
Vol 70 (3) ◽  
pp. 560-565
Author(s):  
Elaine A Bunch
Keyword(s):  
Thin Layer ◽  
Spectrophotometric Determination ◽  
Spectrophotometric Method ◽  
Coefficient Of Variation ◽  
Visible Spectrum ◽  
Interlaboratory Study ◽  
Commercial Products ◽  
Absorbance Maximum

Abstract A previously reported visible spectrophotometric method for the analysis of aminacrine hydrochloride in creams, jellies, and suppositories was studied collaboratively by 8 laboratories. Aminacrine hydrochloride was extracted into acidic ethanol and its visible spectrum recorded. The amount present was calculated by determining the net absorbance between the absorbance maximum at about 402 nm and one-half the sum of the absorbance of the minima at about 389 and 412 nm. Each collaborator received 4 creams (0.2%), 1 jel (0.2%), 1 molded suppository (6 mg/3.198 g), and 2 gelatin-encapsulated suppository samples (12 mg/6.661 g and 14 mg/6.863 g). The cream samples included blind duplicates prepared to contain 0.212% aminacrine hydrochloride, 15% sulfanilamide, and 2% allantoin. Mean recovery for the authentic cream was 104.7% with a coefficient of variation (CV) of 9.22%. The commercial products contained these respective amounts (CVs): creams, 100.0% (2.48%) and 101.5% (2.16%); jel, 118.0% (9.58%); molded suppository, 102.7% (1.88%); and gelatin encapsulated suppositories, 93.1% (1.0%) and 94.3% (1.60%). Standard aminacrine hydrochloride provided for the study was 99.6% pure by nonaqueous titration. Thin layer chromatographic identification of aminacrine hydrochloride was also tested collaboratively. The method was not adopted by AOAC.

Thin Layer Chromatographic Determination of Citrinin

1979 ◽  
Vol 62 (1) ◽  
pp. 201-202 ◽  
Author(s):  
Robert D Stubblefield
Keyword(s):  
Acetic Acid ◽  
Thin Layer ◽  
Linear Relationship ◽  
Silica Gel ◽  
Coefficient Of Variation ◽  
Ethylenediaminetetraacetic Acid ◽  
Limit Of Detection ◽  
Chromatographic Determination ◽  
Tlc Plates

Abstract Clearly defined zones of citrinin can be obtained on thin layer chromatographic (TLC) plates and measured by fluorodensitometry. Silica gel plates were prepared as a slurry with aqueous 0.05M Na2EDTA (ethylenediaminetetraacetic acid), spread at 0.5 mm wet thickness, and activated at 105°C for 1 hr. Plates were developed in acetic acid-benzene (5+95). The limit of detection was 10 ng citrinin/zone. Densitometric analysis (365 nm excitation, 505 nm emission) revealed that a linear relationship exists for levels of 10 ng to at least 100 ng/zone wtih a coefficient of variation of ±5%.

Spectrophotometric determination of bismuth with diethylenetriaminepenta-acetic acid

Talanta ◽  
1978 ◽  
Vol 25 (11-12) ◽  
pp. 691-692 ◽  
Author(s):  
P. Nenova ◽  
D. Kantcheva ◽  
B. Karadakov
Keyword(s):  
Acetic Acid ◽  
Spectrophotometric Determination

Thin Layer Chromatographic Detection and Spectrophotometric Determination of the Trisodium Salt of 1,3,6-PyrenetrisuIfonic Acid in D&C Green No. 8

1984 ◽  
Vol 67 (4) ◽  
pp. 762-763
Author(s):  
Naomi Richfield-Fratz
Keyword(s):  
Thin Layer ◽  
Spectrophotometric Determination ◽  
Chromatographic Method ◽  
Chromatographic Detection ◽  
Trisodium Salt

Abstract A thin layer chromatographic method is presented for separating the reaction by-product 1,3,6-pyrenetrisuIfonic acid (trisodium salt) (PTS) from D&C Green No. 8 (8-hydroxy-l,3,6-pyrenetrisulfonic acid). PTS is detected visually, extracted from the adsorbent, and determined spectrophotometrically. Recoveries of PTS added at 0.75-6.73% levels to 8-hydroxy-l,3,6-pyrenetrisuIfonic acid ranged from 80.0 to 94.8%.

Sign in / Sign up

Export Citation Format

Share Document