Determination of Prednisolone Sodium Phosphate by Ion-Pair Extraction

1974 ◽  
Vol 57 (3) ◽  
pp. 735-737
Author(s):  
Gilbert B Kaplan ◽  
Joseph Levine
Keyword(s):  
Molecular Weight ◽  
Sodium Phosphate ◽  
Methylene Chloride ◽  
Aliphatic Amine ◽  
Sodium Hydroxide Solution ◽  
Ion Pair ◽  
Phosphate Ester ◽  
Ultraviolet Spectrophotometry ◽  
Immobile Phase

Abstract Prednisolone sodium phosphate cannot be extracted as such from aqueous solutions because of its polar characteristics. It can be extracted as its ion pair, using a relatively high molecular weight aliphatic amine as counter ion. Liquid formulations of prednisolone sodium phosphate are rapidly assayed by incorporating the sample as immobile phase in a partition chromatographic column. Prewash with suitable organic solvents removes extractable adjuvants; the phosphate ester is eluted with a solution of trihexylamine hydrochloride in methylene chloride. The ester is extracted from the eluate with sodium hydroxide solution, and measured by ultraviolet spectrophotometry.

scholarly journals Simple Atomic Absorption Spectroscopic and Spectrophotometric Methods for Determination of Pioglitazone Hydrochloride and Carvedilol in Pharmaceutical Dosage Forms

2014 ◽  
Vol 2014 ◽  
pp. 1-17 ◽  
Author(s):  
Afaf A. Abdelmonem ◽  
Gamal H. Ragab ◽  
Hisham Hashem ◽  
Eman A. Bahgat
Keyword(s):  
Atomic Absorption ◽  
Acidic Medium ◽  
Methylene Chloride ◽  
Ion Pair ◽  
Fast Green ◽  
Experimental Conditions ◽  
Pharmaceutical Dosage Forms ◽  
Spectrophotometric Methods ◽  
Orange G

This study represents simple atomic absorption spectroscopic and spectrophotometric methods for determination of pioglitazone hydrochloride (PGZ-HCl) and carvedilol (CRV) based on formation of ion-pair associates between drugs and inorganic complex, bismuth(III) tetraiodide (Method A) and between drugs and organic acidic dyes, fast green and orange G (Method B). Method A is based on formation of ion-pair associate between drugs and bismuth(III) tetraiodide in acidic medium to form orange-red ion-pair associates, which can be quantitatively determined by two different procedures. The formed ion-pair associate is extracted by methylene chloride, dissolved in acetone, dried, and then decomposed by hydrochloric acid, and bismuth content is determined by direct atomic absorption spectrometric technique (Procedure 1) or extracted by methylene chloride, dissolved in acetone, and quantified spectrophotometrically at 490 nm (Procedure 2). Method B is based on formation of ion-pair associate between drugs and either fast green dye or orange G dye in acidic medium to form ion-pair associates. The formed ion-pair associate is extracted by methylene chloride and quantified spectrophotometrically at 630 nm (for fast green dye method) or 498 nm (for orange G dye method). Optimal experimental conditions have been studied. Both methods are applied for determination of the drugs in tablets without interference.

scholarly journals Spectrophotometric Determination of Thioridazine Hydrochloride in Tablets and Biological Fluids by Ion-Pair and Oxidation Reactions

2012 ◽  
Vol 27 ◽  
pp. 129-141 ◽  
Author(s):  
Akram El-Didamony ◽  
Sameh Hafeez
Keyword(s):  
Methylene Chloride ◽  
Biological Fluids ◽  
Indigo Carmine ◽  
Ion Pair ◽  
Bromocresol Green ◽  
Official Method ◽  
Bromocresol Purple ◽  
Accuracy And Precision ◽  
Significant Difference

Two simple, sensitive and selective spectrophotometric methods have been described for the determination of the psychoactive drug, thioridazine HCl in tablets and in biological fluids. The first method is based on the oxidation of thioridazine HCl with measured excess of KMnO4under acidic conditions followed by the determination of unreacted oxidant using indigo carmine and methyl orange. The second method is based on the formation of ion-pair complexes with the acidic sulphophthalein dyes such as bromocresol green and bromocresol purple at pH 1.8 of KCl-HCl buffer. The formed complexes were extracted into methylene chloride and their absorbance was measured at 412 nm. Optimizations of the different experimental conditions are described for both methods. The proposed methods were successfully applied for determination of the drug in tablets and biological fluids with good accuracy and precision. Statistical comparison of the results with those obtained by an official method showed good agreement and indicated no significant difference in accuracy and precision.

Determination of Diuron in Wheat

1973 ◽  
Vol 56 (4) ◽  
pp. 831-833 ◽  
Author(s):  
Constantin Parouchais
Keyword(s):  
Carbon Tetrachloride ◽  
Petroleum Ether ◽  
Analytical Procedure ◽  
Methylene Chloride ◽  
Phase 1 ◽  
Soxhlet Extraction ◽  
Alternative Technique ◽  
Wheat Grain ◽  
Ultraviolet Spectrophotometry

Abstract A simplified analytical procedure is described for the determination of diuron residues in a large number of wheat grain samples. The sample is subjected to Soxhlet extraction with acetone, the extract is dissolved in an acetone-aqueous phase (1+5) and then extracted with petroleum ether, and diuron is extracted into methylene chloride and carbon tetrachloride. Electron capture GLC is the determinative step, with ultraviolet spectrophotometry as an alternative technique.

Determination of vanillylmandelic acid with ion-pair chromatography and fluorescence detection.

1986 ◽  
Vol 32 (4) ◽  
pp. 693-696 ◽  
Author(s):  
K Lindgren ◽  
N Rodopoulos
Keyword(s):  
Internal Standard ◽  
Reversed Phase ◽  
Ion Pair ◽  
Fluorescence Signal ◽  
Vanillylmandelic Acid ◽  
Ultraviolet Spectrophotometry ◽  
Ion Pair Chromatography ◽  
Chromatographic Procedure ◽  
The Mean

Abstract We describe a chromatographic procedure for sensitive (2.0 mumol/L), specific quantification of vanillylmandelic acid (VMA) in urine with iso-VMA as an internal standard. After rapid extraction from urine, the VMA is determined by isocratic reversed-phase ion-pair chromatography on a bonded C8 column and detection of the native fluorescence on excitation at 285 nm. The fluorescence signal is quite dependent on the pH of the mobile phase. Results by the method vary linearly with VMA concentration up to 320 mumol/L and correlate well (r = 0.9880) with those obtained by conventional ultraviolet spectrophotometry. The mean 24-h excretion of VMA from 29 healthy volunteers was 21.4 (SD 5.4) mumol.

Spectrophotometric Determination of the Styrene Content of Butadiene-Styrene Copolymers

1946 ◽  
Vol 19 (4) ◽  
pp. 1077-1084 ◽  
Author(s):  
E. J. Meehan
Keyword(s):  
Molecular Weight ◽  
Spectrophotometric Determination ◽  
Extinction Coefficient ◽  
Ultraviolet Spectrophotometry ◽  
Relative Precision ◽  
Specific Extinction Coefficient ◽  
Styrene Copolymers ◽  
Styrene Content ◽  
Butadiene Styrene

Abstract The ultraviolet absorption of polystyrene, with maximum absorption at 262 mµ, is due to the presence of phenyl residues in the polymer. The specific extinction coefficient is constant, i.e., independent of the molecular weight of the polymer. This shows that the extinction of the phenyl residues is additive. On the basis of this fact, it is shown that the styrene content of a butadiene-styrene copolymer (such as GR-S rubber) can be determined by ultraviolet spectrophotometry. The relative precision of the determination is about 1 per cent, the probable relative accuracy is about 3 per cent.

The External Shape of Human γ GI Immunoglobulin from Crystal Sections

1971 ◽  
Vol 29 ◽  
pp. 428-429
Author(s):  
L. W. Labaw
Keyword(s):  
Molecular Weight ◽  
Sodium Phosphate ◽  
Osmium Tetroxide ◽  
Unit Cell ◽  
Monoclinic Space Group ◽  
X Ray ◽  
Large Molecular Weight ◽  
Cell Dimensions ◽  
Unit Cell Dimensions ◽  
Crystallographic Axes

Crystals of a human γGl immunoglobulin have the external morphology of diamond shaped prisms. X-ray studies have shown them to be monoclinic, space group C2, with 2 molecules per unit cell. The unit cell dimensions are a = 194.1, b = 91.7, c = 51.6Å, 8 = 102°. The relatively large molecular weight of 151,000 and these unit cell dimensions made this a promising crystal to study in the EM.Crystals similar to those used in the x-ray studies were fixed at 5°C for three weeks in a solution of mother liquor containing 5 x 10-5M sodium phosphate, pH 7.0, and 0.03% glutaraldehyde. They were postfixed with 1% osmium tetroxide for 15 min. and embedded in Maraglas the usual way. Sections were cut perpendicular to the three crystallographic axes. Such a section cut with its plane perpendicular to the z direction is shown in Fig. 1.This projection of the crystal in the z direction shows periodicities in at least four different directions but these are only seen clearly by sighting obliquely along the micrograph.

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