HPLC Analysis of Injectable Contraceptive Preparation Containing Norethisterone Enanthate and Estradiol Valerate

Abstract

A simple, accurate method for simultaneous determination of norethisterone enanthate (NET-EN) and estradiol valerate (EV) in the injectable is reported. An improved extraction procedure for steroid esters from the oily formulation was developed. Recoveries of 100.6 and 98.7% were obtained for NET-EN and EV.     

Gas-chromatographic determination of a mixture of testosterone and oestradiol esters in oily injection

Summary A gas-liquid chromatographic method is described for the determination of testosterone and oestradiol esters in oily injection. The separation of the steroids from the injection is performed by partition in the acetonitrile-hexane system. For gas chromatography the oestradiol esters were preliminary transformed to their mono-TMS derivatives. For the separation Dexsil 400 was preferably used as stationary phase. Mestranol was employed as internal standard for quantitation. A complete separation for all the individual components can be achieved within 12 min. The relative standard deviation is in the range of 1–1.5%.

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Gas-chromatographische Bestimmung eines Gemisches von Testosteron- und Östradiolestern in öliger Injektionslösung

Zusammenfassung Die Abtrennung der Steroide aus der Injektionslösung erfolgt durch Extraktion mit Acetonitril und n-Hexan. Zur Gas-Chromatographie werden die Östradiolester in die Mono-trimethylsilylderivate übergeführt. Als stationäre Phase dient vorzugsweise Dexsil 400. Zur quantitativen Bestimmung wird Mestranol als inneren Standard benutzt. Eine vollständige Trennung der Ester läßt sich innerhalb von 12 min erreichen. Die relative Standardabweichung liegt im Bereich von 1–1,5%.

     

Histochemical Chromatography A New Technique for Identifying Crystal and Oily Components in Cell Tissue by Combination of a Micromanipulator and HPLC

Abstract

The constituents of oil droplets in clove (bud of Eugenia caryophyllata) cell and crystals of berberine alkaloids in bark cell in Phellodendron amurense were transfered into a microcapillary glass tube attached to a micromanipulator apparatus and analysed by HPLC. The method makes it possible to identify components in cells as long as they are in an oily or crystalline state. This new ultramicro-technique is entitled “Histochemical Chromatography”.     

The Use of Electrospray Mass Spectrometry (ES/MS) for the Differential Detection of Some Steroids as Calix-[n]-arene Sulphonate Complexes

Non-covalent inclusion complexes formed between three p-sulphonato-calix-[n]-arenes (1 n = 4, 2 n = 6 and 3 n = 8) and three steroids (progesterone, testosterone and oestradiol) have been studied by electrospray mass spectrometry (ES/MS). Mass spectrometric titration experiments have demonstrated differences with regard to selectivity of each p-sulphonato-calix-[n]-arene against the steroids. p-sulphonato-calix-[8]-arene interacts more strongly with oestradiol and p-sulphonato-calix-[6]-arene with progesterone. Studies in which different orifice voltages were applied show that all oestradiol complexes are reduced in signal intensity at 50 V as compared to 20 V, whereas the intensities observed for the testosterone and progesterone complexes do not vary with voltage. Competition experiments confirm the selectivity of the complexation.     

A gas chromatographic flow method for preconcentration and determination of vitamins D2 and D3 in pharmaceutical preparations

Summary A continuous-flow method that combines on-line preconcentration and isolation with gas chromatography for the direct determination of vitamins D₂ and D₃ in oily solutions is reported. A silica gel column permits preconcentration and isolation of analytes from the vitamin D matrix, although some triglyceride (ca. 25%) is also retained. To overcome problems associated with the low volatility of triglycerides, their retained fraction is further transesterified with potassium methylate to fatty acid methyl esters after elution. The proposed method was applied to the determination of vitamin D in pharmaceutical preparations.     

Determination of Rutin in Plant Extracts and Emulsions by HPLC-MS

A method for the determination of rutin was developed from in an O/W emulsion with decyl oleate and Ceteareth-20 containing Ginkgo biloba L., Hedera helix L., and Thymus vulgaris L. extracts. Total quantification of rutin was performed by determination in the aqueous and oily phase. Rutin was extracted from the oily phase by ultrasonication for 30 min at 37°C in methanol and resolved by liquid chromatography on a column containing a Gemini 3 µ C18 110A stationary phase.

Chromatography was carried out using gradient elution with the mobile phase composed of water:formic acid and water:acetonitrile:formic acid, which was varied from 100:0.1 to 50:50:0.1 (v/v/v) over 80 min and delivered at a flow rate of 0.3 ml/min. The analytes were quantified using a UV-VIS absorption spectrometer at a wavelength of 254 nm and a single quadrupole mass spectrometer employing an ESI interface operated in the positive ion mode with single ion monitoring at m/z = 609.14.

Finally, a simple and rapid method for the extraction and determination of rutin in hydrophilic and lipophilic phases of an O/W emulsion with good precision and acceptable recovery was developed. This method might be of special importance for the analysis of rutin and other flavonoids in O/W or W/O emulsion matrices.     

Analytical Characterization of Fatty Acids Composition of Bioactive Stem Oil of Maytenus royleanus by Gas Chromatography Mass Spectrometry

The significant inhibition and selectivity for human solid tumor cell by oily fraction of Maytenus royleanus, was subjected to GC‐MS analysis for determination of its chemical constituents. GC‐MS profile of methyl ester derivatives of fatty acids, showed that Palmitic acid (35.41%), Oleic acid (10.91%), Stearic acid (5.31%), Margaric acid (5.13%), Behenic acid (5.18%) and Hexanoic acid (4.97%) were the major components in the isolated oily fraction, while rest of the other fatty acids were present in minor concentration. The literature revealed that no such work has been done for the determination of fatty acids in M. royleanus stem oil.     

Simultaneous Analysis Of Estradiol Dienanthate,Estradiol 3-Benzoate And Testosterone Enanthate Benzilic Acid Hydrazone In Oily Formulations Bygradient-Hplc

Abstract

A procedure is described for the analysis of estradiol-3-benzoate, testosterone enanthate benzylic acid hydrazone and estradiol dienanthate in oily solution. The multi-step gradient reversed phase ion-pairing HPLC method uses 1-pentane sulfonic acid sodium salt (0.0025 M in 0.1% acetic acid methanolic solution): acetonitrile and water (55 : 30 to 45 : 15 to 0) mobile phase gradient and a 250 × 4.6 mm, 5 micron octadecyl silane column, with 1,2,4,5-tetrachlorobenzene as internal standard. The time required for chromatography is 31 minutes. The method gives relative standard deviations (RSD) of .94% or better for the assay of active ingredients in commercial formulations.     

Determination of Arteether in Plasma Using a Simple and Rapid High-Performance Liquid Chromatographic Assay

Abstract

A simple and rapid high-performance liquid chromatographic (HPLC) assay for the determination of the antimalarial drug arteether in plasma was developed and validated in this report. Perchloric acid was used in this method as a plasma protein precipitant and to attain an acidic medium suitable for the decomposition of arteether to a derivative possessing UV absorption. This derivative and the internal standard (progesterone) were separated from the plasma on a 10 μm μ-Bondapack C₁₈ reversed-phase column at ambient temperature with a mobile phase composed of acetonitrile:water (60:40 v/v) and at a flow rate of 1.5 ml/min. The effluent was monitored at 254 nm with a UV detector. Linear relation between drug concentrations and peak height ratios of arteether derivative to the internal standard was achieved in the range of 0.25-10 μg/ml arteether with a detection limit of 50 ng/ml arteether in plasma. The within-day and between-days precisions were evaluated using 3 different concentrations of arteether. The values of the coefficients of variation were 1.35-1.68% and 1.65-2.82% for within-day and between-day, respectively. This method was applied to determine some pharmacokinetic parameters of arteether after intramuscular injection of 50 mg/kg arteether oily solution to rabbits.     

Determination of Hg in water and wastewater samples by CV-AAS following on-line preconcentration with silver trap

An online mercury preconcentration and determination system consisting of cold vapor atomic absorption spectrometry (CV-AAS) coupled to a flow injection (FI) method was studied. The method was developed involving the determination of ng/L levels of mercury retained on the silver wool solid sorbent. Experimental conditions such as sample volume, flow rate, stability of the column and effect of foreign ions on the determination of trace amounts of mercury were optimized. The detection limit is 3 ng/L and dynamic range 10–250 ng/L require only 50 mL of sample. The relative standard deviations (RSD) of the determinations are below 4%. The presence of common metal ions, such as K+, Na⁺, Cu²⁺, Pb²⁺, Fe³⁺, Ni²⁺, and Mn²⁺, does not interfere with the measurement of mercury by this method. The method was successfully applied to the determination of mercury in water and wastewater samples.     

Indirect Determination of Organic Compounds by Atomic Absorption Spectrophotometry: The Study of Vitamin B12 in Pharmaceutical Dosage Forms

Abstract

A method for the determination of vitamin B₁₂ in pharmaceutical dosage forms is presented. The method involves, dissolution of the vitamin B₁₂ and subsequent determination of the complexed cobalt by atomic absorption spectrophotometry. The method is both rapid and sensitive giving applications to quality, control of this type of formulation.     

Simultaneous Ultraviolet Spectrophotometric Determination of Nitrate and Nitrite in Water

Abstract

A rapid and accurate method for the direct simultaneous determination of nitrate and nitrite is proposed. The method is applied to the determination of nitrate and nitrite in rainwater and wastewater without preliminary separation. The determinations are performed by a CPA matrix method with ultraviolet spectrophotometric detection. The results obtained are in agreement with those obtained by conventional methods for the determination of nitrate and nitrite.     

Batch and Flow Injection Fluorimetric Determination of Fluoxetine

Abstract

A method for the fluorimetric determination of fluoxetine in continuous and discontinuous systems is reported. The method is based on the hydrolysis of fluoxetine in acid medium. The fluorescent product has a spectrum with excitation and emission maxima at 253 and 306 nm, respectively. The method was applied to the determination of fluoxetine in pharmaceutical products.     

Semiquantitative and Quantitative Determination of Trace Amount of Phosphate Ion in Water Using Polyurethane Foam Thin -Layer Colorimetry

Abstract

A simple, sensitive and fast method for the colorimetric determination of phosphate ion in water is described.

The method is based on spectrophotometric measurement of the blue molybdoantimony phosphoric acid species sorbed in a polyurethane foam thin-layer for quantitative determination of phosphate ion, or the visual color comparison technique for rapid semiquantitative determination.

The detection limit for the quantitative procedure is 5 μg/1 and for semiquantitative procedure 20 μg/1 for sample volumes of 100 ml and 25 ml, respectively.     

Determination of Creatinine in Plasma by the Apparent Content Curves Method

Summary

A mathematical method that avoids spectral interferences in creatinine determination in plasma by the Jaffé reaction is proposed. The experimental conditions are studied and the accuracy and precision of the method are tested against two reference methods. The proposed method provides good results and it is suitable for creatinine determination in plasma.     

Extractive Spectrqphotometric Determination of Vanadium Liith o-Aminobenzo-Hydroxamic Acid

Abstract

A new spectrophotometric method for vanadium determination is proposed. The method is based on the extraction in Adogen-toluene solution of the complex formed between V(V) and o-Aminobenzohydraxámic acid

The method allows determination of 50 to 110 μg of V(V). The error and the apparent molar absorptivity are 1.2% and 5.2 ± 10³ l.mol^?1. cm^?1 respectively. The interferences caused by foreign ions have been established. The method is applied with success to determination of vanadium in petroleum crudes.     

A Fluorescence Quenching Method for the Determination of Chromium(VI) with L-Tyrosine

Abstract

A fluorescence quenching method for the determination of Cr(VI) in aqueous solution is described. The fluorescence intensity of the system is linear ever the range 5×10^?6 - 1.0×10^?4 M Cr(VI). The method has been applied to the determination of Cr(VI) In cast iron and waste water.     

The Determination of Cyclohexylamine in Aqueous Solutions of Sodium Cyclamate by Electron-Capture Gas Chromatography

Abstract

A sensitive primary amine assay, capable of detecting 10^?11 g. and utilizing the determination of the amine N-2, 4-dinitrophenyl derivative by electron-capture gas chromatography is described. The method is exemplified by the determination of cyclohexylamine in sodium cyclamate.     

A FACIAL SYNTHESIS OF THE NEUTRAL [1,2,4]TRIAZOLO- [3,2-d][1,5]BENZOXAZEPINES AND THEIR CHALCOGEN-ANALOGUES

ABSTRACT

An expedient synthesis of neutral [1,2,4]triazolo[3,2-d][1,5]-benzoxazepines 6a–e and their chalcogen analogues 6f–i was accomplished via cycloaddition of the heterocumulene cations (3a,b), generated sequentially by action of chroman-4-one as well as thiochroman-4-one ethoxy carbonylhydrazones (1a,b) with t-BuOCl and SbCl₅, to the triple bond of nitriles and concurring ring enlargement and hydrolytic removal of the N(1)-ethoxycarbonyl group. The oily final products were characterized as their picrates.     

Application of Flow Injection Method for the Determination of Thioridazine

Abstract

A simple flow-injection spectrophotometric method for the determination of thioridazine is described. The method is based on the oxidation of thioridazine with phosphotungstic acid in hydrochloric acidic media. Concentrations of thioridazine in the range 10 – 60 ppm are determined with a relative standard deviation of 1.1%. The method was applied to the determination of thioridazine in pharmaceutical formulations.