scholarly journals THE INVESTIGATION OF CONDITIONS OF API FROM GROUP OF CALCIUM CHANNEL BLOCKERS EXTRACTION BY ORGANIC SOLVENTS BY USING HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY AS ASSAY METHOD

2017 ◽  
Vol 10 (10) ◽  
pp. 354
Author(s):  
Olgya Polyauk ◽  
Liliya Logoyda
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Calcium Channel ◽  
Organic Solvents ◽  
Calcium Channel Blockers ◽  
High Performance ◽  
Research Work ◽  
Assay Method ◽  
Channel Blockers ◽  
Water Solutions

  Objective: The objective of this research was to select the optimal conditions for extraction of API from calcium channel blockers (amlodipine, nifedipine, and verapamil) by organic solvents from water solutions in dependence on pH solutions.Methods: The chromatographic analysis of amlodipine, nifedipine, and verapamil performed on liquid chromatography Agilent 1200.Results: The quantitative determination of API from calcium channel blockers (amlodipine, nifedipine, and verapamil) by high-performance liquid chromatography - method has been conducted. As a result of studies, we have found that the optimal extragent is chloroform, which is extracted at pH 7-82.1% of amlodipine, pH 5-76.2% of nifedipine, and pH 8-95.1% verapamil hydrochloride. API from calcium channel blockers (amlodipine, nifedipine, and verapamil) least extracted with hexane at pH 2.0, so these conditions may be cleaned extract from coextractives impurities.Conclusion: The results obtained in this research work clearly indicated that the extraction of API from calcium channel blockers (amlodipine, nifedipine, and verapamil) by organic solvents from water solutions in dependence on pH solutions has been conducted.

Specific serum quinidine assay by high-performance liquid chromatography.

1977 ◽  
Vol 23 (11) ◽  
pp. 2030-2033 ◽  
Author(s):  
W G Crouthamel ◽  
B Kowarski ◽  
P K Narang
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Raw Materials ◽  
Therapeutic Index ◽  
Assay Method ◽  
Cardioactive Drug ◽  
Double Extraction ◽  
Serum Quinidine

Abstract The cardioactive drug quinidine has a narrow therapeutic index; consequently, determination of serum quinidine concentrations can be important. We describe a relatively rapid and specific assay for quinidine in serum by high-performance liquid chromatography. It is suitable for use in patient monitoring or pharmacodynamic studies. Alkalinized serum is extracted with benzene, which is evaporated under nitrogen and reconstituted with methanol; an aliquot is chromatographed. Quinidine is separated from its metabolites and dihydroquinidine (a contaminant in quinidine raw materials). The retention time for quinidine is 4 min 10 s, for dihydroquinidine it is 5.5 min. Results for patients' sera by this assay method and the double-extraction method of Cramer and Isaksson [Scand. J. Clin. Lab. Invest. 15, 553 (1963] correlate well (r = .975).

scholarly journals Estradiol Solubility in Aqueous Systems: Effect of Ionic Concentrations, pH, and Organic Solvents

2013 ◽  
Vol 2013 ◽  
pp. 1-4 ◽  
Author(s):  
John E. A. Carter ◽  
Patrick M. Sluss
Keyword(s):  
Breast Cancer ◽  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Human Serum ◽  
Clinical Significance ◽  
Organic Solvents ◽  
Diethyl Ether ◽  
High Performance ◽  
Reverse Phase ◽  
Concentration Levels

This study examined the effects of ionic strengths of NaCl (0.1, 0.3, and 1.0 M), pH (3, 7, and 11), and organic solvents (dichloromethane, diethyl ether, and methanol) on the extraction of estradiol at concentrations of 5.0 pg/mL in human serum. Methanol extracted almost 100% of the estradiol at a 5.0 pg/mL concentration, while ether and dichloromethane extracted only 73% or 70%, respectively, of the estradiol. The methanol extracted material was subjected to reverse phase high-performance liquid chromatography (HPLC) using 60% methanol and was found to elute at the same position as estradiol standard. These results suggest that methanol extraction of estradiol may prove useful in situations where estradiol occurs at concentration levels of ≥5.0 pg/mL, concentrations of great clinical significance in the detection and treatment of breast cancer.

scholarly journals A Validated specific Stability-Indicating Reversed-Phase High-Performance Liquid Chromatography Assay Method for L-Ornithine L-Aspartate and Silymarin, and their related Substances and its Application to Dissolution Studies

2020 ◽  
Vol 11 (03) ◽  
pp. 317-328
Author(s):  
Prasada Rao Kammela ◽  
Bhavani Podili ◽  
Mohan Seelam
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Mobile Phase ◽  
High Performance ◽  
Reversed Phase ◽  
Dosage Forms ◽  
Assay Method ◽  
Active Components ◽  
Stability Indicating ◽  
Related Substances

The present study was aimed at the development and successive validation of a novel, simple, sensitive, and stability-indicating reversed-phase high-performance liquid chromatography (RP-HPLC) method for quantitative calculation of L-ornithine L-aspartate (LOLA) and Silymarin (SL), and also their relevant substances in bulk and pharmaceutical dosage forms. The chromatographic technic was optimized using the impurity-spiked solution. The separation of all the two active components and their impurities was achieved by a chromatographic method with an Agilent Eclipse XDB-C18, 150 × 4.6 mm, 3.5 μ column, using gradient elution with mobile phase A consisting of a mixture of 0.1% orthophosphoric acid and water and acetonitrile as mobile phase B. The instrumental settings included a flow rate of 1 mL/min for both related substances and assay, a detector wavelength of 225 nm, by using a PDA detector. The established method was validated according to the current ICH requirements. The detection limit and the limit of quantification for the two active components and their related impurities were established with respect to test concentration. The calibration graphs plotted were linear with a regression coefficient R2 andgt; 0.999, indicates the linearity of the method was within the limits. Recovery studies were satisfactory and the parameters, such as, specificity, linearity, accuracy, precision, and robustness were determined as part of the method validation. Moreover, using the same method dissolution study was performed on active pharma ingredients to estimate the recovery. The obtained results were within the range of acceptance criteria. These results suggest that the developed method was found to be applicable for routine analysis for testing chromatographic purity of LOLA and SL and it can be utilized for the calculation of both active ingredients and their impurities in tablet dosage forms.

Sign in / Sign up

Export Citation Format

Share Document