scholarly journals Development of new HPLC method for identification of metabolic degradation of N-pyrrolylhydrazide hydrazones with determined MAO- B activity in cellular cultures

Pharmacia ◽  
2022 ◽  
Vol 69 (1) ◽  
pp. 15-20
Author(s):  
Alexandrina Mateeva ◽  
Lily Peikova ◽  
Magdalena Kondeva-Burdina ◽  
Maya Georgieva

In this research, a new rapid PR- HPLC method was developed for the determination of metabolites in isolated rat hapatocytes. The chromatographic parameters, including the stationary and mobile phases, outlet pressure, temperature and flow rate, were optimized. The method identified two initial from the synthesis molecules in higher concentration and one new unidentified structure as products of the hepatocytic processing of the evaluated analyte. The results identified as first step of metabolism the hydrolysis of the hydrazone group. Further investigations should be aimed into determining the next metabolic transformations, predicted by the in silico application of the web server SMARTCyp.

2010 ◽  
Vol 75 (11) ◽  
pp. 1583-1594 ◽  
Author(s):  
Miroslav Milenkovic ◽  
Valentina Marinkovic ◽  
Predrag Sibinovic ◽  
Radosav Palic ◽  
Dragan Milenovic

An HPLC method for digoxin quantification in dissolution samples obtained as per the official British Pharmacopeia (BP) method is presented in this paper. The chromatography was performed at 20 ?C on a Symmetry C18; 3.5 ?m, 75 x 4.6 mm column with water - acetonitrile (72 : 28, v/v), as the mobile phase and UV detection at 220 nm. The method was found to be selective, linear, accurate and precise in the specified ranges. The LOD and LOQ were 0.015 ?g mL-1 and 0.050 ?g mL-1, respectively. Robustness testing was conducted to evaluate the impact of minor changes in the chromatographic parameters (i.e., acetonitrile fraction, flow rate of the mobile phase, column temperature and column length) on the characteristics of the digoxin peak. A. full factorial design (24) was used to investigate the influence of the four variables The presented HPLC method was applied in quality and stability testing of Digoxin tablets 0.25 mg.


2012 ◽  
Vol 9 (3) ◽  
pp. 1165-1174 ◽  
Author(s):  
L. Maheshwara Reddy ◽  
K. Janardhan Reddy ◽  
L. Bhaskar Reddy ◽  
P. Raveendra Reddy

A chromatographic method was established for the determination of lenalidomide and related substances in 10 mg and 5 mg capsules using Sunfire C-18(250×4.6 mm ID, 5 μm) HPCL column with 85:15 v/v ratio of mobile phases A (mixture of phosphoric acid buffer and 1-octane sulphonic acid sodium salt) and B(55: 45 v/v ratio of methanol and acetonitrile) at 40°C and 210 nm wave length. The degradation studies were performed using 0.1N HCl, 0.1 N NaOH, 1% v/v hydrogen peroxide, humidity, UV at 254 nm, Sun light, and heat to 60°C. No significant degradation of lenalidomide was observed. However, the slight degradation was observed in presence of NaOH. The developed HPLC method gave the peaks purity angle was less their threshold angle, indicating it to be suitable for stability studies. It was validated with respect to linearity, accuracy, precision, ruggedness, and robustness.


2001 ◽  
Vol 47 ◽  
pp. 9-14
Author(s):  
Svetlana Kulevanova ◽  
Marina Stefova ◽  
Tatjana Kadifkova Panovska ◽  
Jasmina Tonic ◽  
Trajce Stafilov

Assay of flavonoids in extracts of seven Thymus L. (Lamiaceae) species from Macedonia including identification and quantification was performed. Extracts obtained after hydrolysis of air dried samples (A1) were analyzed by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). Luteolin and apigenin were identified in comparison to authentic standard substances. The content of total flavonoids in plant samples determined by UV-Vis spectrometry (with AlCl3) ranged from 0.05-0.13 %. Two other extracts were prepared by extraction with a mixture of ethanol:water (7:3, V/V), evaporation until only water remained and extraction first with diethylether (A2) and secondly with ethyl acetate (A3). The content of flavonoids in diethyl-ether and ethyl acetate extracts ranged from 52.5-244.4 mg·ml-1 and 48.7 -117.5 mg·ml-1, respectively. For quantification of luteolin and total flavonoids the HPLC method was applied, using reverse phase column C18, mobile phase consisting of 5% acetic acid and methanol in gradient elution mode and column temperature set to 40 o C. The content of luteolin in the plant samples ranged from 0.23-0.48 % (m/m), while the content of total flavonoids was found to be 0.26-0.52 %.


2009 ◽  
Vol 92 (2) ◽  
pp. 410-418 ◽  
Author(s):  
Izabela Fecka

Abstract Thin-layer chromatography (TLC) and liquid chromatography (LC) methods were developed for the qualitative and quantitative determination of agrimoniin, pedunculagin, ellagic acid, gallic acid, and catechin in selected herbal medicinal products from Rosaceae: Anserinae herba, Tormentillae rhizoma, Alchemillae herba, Agrimoniae herba, and Fragariae folium. Unmodified silica gel (TLC Si60, HPTLC LiChrospher Si60) and silica gel chemically modified with octadecyl or aminopropyl groups (HPTLC RP18W and HPTLC NH2) were used for TLC. The best resolution and selectivity were achieved with the following mobile phases: diisopropyl etheracetoneformic acidwater (40 30 20 10, v/v/v/v), tetrahydrofuranacetonitrilewater (30 10 60, v/v/v), and acetoneformic acid (60 40, v/v). Concentrations of the studied herbal drugs were determined by using a Chromolith Performance RP-18e column with acetonitrilewaterformic acid as the mobile phase. Determinations of linearity, range, detection and quantitation limits, accuracy, precision, and robustness showed that the HPLC method was sufficiently precise for estimation of the tannins and related polyphenols mentioned above. Investigations of suitable solvent selection, sample extraction procedure, and short-time stability of analytes at storage temperatures of 4 and 20C were also performed. The percentage of agrimoniin in pharmaceutical products was between 0.57 and 3.23.


2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Muhammad Jehangir ◽  
Mahmood Ahmed ◽  
Muhammad Imtiaz Shafiq ◽  
Abdul Samad ◽  
Iftikhar-ul-Haq

A newly developed method based on ultrahigh performance liquid chromatography (UHPLC) was optimized for the simultaneous determination of vitamin D3and menaquinone-7 (MK-7) in tablet formulation in the present study. UHPLC separation of vitamin D3and MK-7 was performed with ACE Excel 2 C18-PFP column (2 μm, 2.1×100 mm) at 0.6 mL min−1flow rate, whereas the mobile phase consisted of methanol/water (19:1, v/v, phase A) and isopropyl alcohol (99.9%, phase B) containing 0.5% triethylamine. Isocratic separation of both the analytes was performed at 40°C by pumping the mobile phases A and B in the ratio of50:50(v/v, pH, 6.0). Both analytes were detected at a wavelength of 265 nm and the injection volume was 1.0 μL. The overall runtime per sample was 4.5 min with retention time of 1.26 and 3.64 min for vitamin D3and MK-7, respectively. The calibration curve was linear from 5.0 to 100 μg mL−1for vitamin D3and MK-7 with a coefficient of determination (R2)≥0.9981, while repeatability and reproducibility (expressed as relative standard deviation) were lower than 1.46 and 2.21%, respectively. The proposed HPLC method was demonstrated to be simple and rapid for the determination of vitamin D3and MK-7 in tablets.


Author(s):  
Jaap Schrijver ◽  
Andries J Speek ◽  
Jan A Klosse ◽  
Herman J M Van Rijn ◽  
Wil H P Schreurs

A sensitive and reliable method for the determination of total thiamine (vitamin B1) in whole blood has been developed which is suited for routine analysis. After extraction, and enzymatic hydrolysis of thiamine phosphate esters, thiamine is separated from interfering compounds by a fully automated high-performance liquid chromatographic (HPLC) system. Thiamine is detected fluorometrically as thiochrome. By calculating the concentration of thiamine on-line with the aid of a computer, it is possible to complete one analysis within four hours. Routine thiamine determinations can be carried out in a series of 120 samples within 48 hours. The within-assay and between-assay coefficients of variation of the analysis of total thiamine in whole blood were 4·2 and 4·4%, respectively. The between-assay analytical recovery of thiamine diphosphate added to blood samples was 99·9 ± 11·7% (mean ± SD). The HPLC method described has been applied also to the analysis of thiamine in plasma and erythrocytes. In agreement with other reports, it was found that about 80% of total thiamine of whole blood is present in the erythrocytes. Reference values of thiamine in whole blood of the human were found in the range 95–155 nmol/l.


2016 ◽  
Vol 81 (10) ◽  
pp. 1171-1181 ◽  
Author(s):  
Vladimir Dobricic ◽  
Natasa Bubic-Pajic ◽  
Bojan Markovic ◽  
Sote Vladimirov ◽  
Snezana Savic ◽  
...  

Development and validation of a liquid chromatography - tandem mass spectrometry (LC-MS/MS) method for the determination of adapalene in pharmaceutical forms for skin application were presented. The MS/MS analysis of adapalene was performed by use of three mobile phases, consisted of acetonitrile and (a) 0.1 % formic acid, (b) 0.1 % trifluoroacetic acid and (c) 20 mM ammonium acetate. The strongest signals of parent ion and dominant product ion were obtained in negative mode by use of the mobile phase (c). Validation of this method was performed according to the ICH guidelines. Small variations of selected chromatographic parameters (concentration of ammonium acetate, mobile phase composition, column temperature and flow rate) did not affect qualitative and quantitative system responses significantly, which proved method?s robustness. The method is specific for the determination of adapalene. Linearity was proved in the concentration range 6.7 - 700.0 ng mL-1 (r = 0.9990), with limits of detection and quantification 2.0 ng mL-1 and 6.7 ng mL-1, respectively. Accuracy was confirmed by calculated recoveries (98.4 % - 101.5 %). Precision was tested at three levels: injection repeatability, analysis repeatability and intermediate precision. Calculated relative standard deviations were less than 1, 2 and 3 %, respectively.


1999 ◽  
Vol 81 (2) ◽  
pp. 107-112 ◽  
Author(s):  
H. P. S. Makkar ◽  
K. Becker

The method of Zinn & Owens (1986;Canadian Journal of Animal Science66, 157–166), based on release of purine bases by HClO4followed by their precipitation with AgNO3, was used to study recovery of purines from lyophilized rumen microbial orEscherichia colipreparations added to matrices such as cellulose, starch and neutral-detergent fibre. The recovery of purines was poor (approximately 50 %). Under the hydrolysis conditions (12 M-HClO4, 90–95° for 1 h) used in the method of Zinn & Owens (1986), the recovery of purines from the rumen microbial preparations added to matrices measured using an HPLC method was 95–102 %, suggesting that the lower recovery of purines in the method of Zinn & Owens (1986) was not due to incomplete hydrolysis of nucleic acids. Using the HPLC method, adenine and allopurinol (an internal standard) were found to be heat-labile as substantial destruction was observed on heating at 121°. On the other hand, another commonly used internal standard, caffeine, was stable at 121°. A complete hydrolysis of nucleic acids from the rumen microbial preparation was observed with 2·5 ml 0·6 M-HClO4in a total volume of 3 ml (0·5 M-HClO4during hydrolysis) at 90–95° for 1 h, and under these conditions adenine, guanine, allopurinol and caffeine were stable. Moreover, under these milder hydrolysis conditions, the recovery of purine bases from the rumen microbial orE. colipreparations added to matrices ranged from 92 to 108 % using the method of Zinn & Owens (1986). Based on the results, changes in hydrolysis conditions have been proposed for accurate determination of purine bases using spectrophotometric or HPLC methods.


2016 ◽  
Vol 66 (4) ◽  
pp. 479-490 ◽  
Author(s):  
Said A. Hassan ◽  
Eman S. Elzanfaly ◽  
Salem Badr A. El-Zeany ◽  
Maissa Y. Salem

Abstract Two methods were developed for separation and quantitation of amlodipine (AML) and atorvastatin (ATV) in the presence of their acidic degradation products. The first method was a simple isocratic RP-HPLC method while the second was capillary electrophoresis (CE). Degradation products were obtained by acidic hydrolysis of the two drugs and their structures were elucidated for the first time by IR and MS spectra. Degradation products did not interfere with the determination of either drug and the assays were therefore stability-indicating. The linearity of the proposed methods was established over the ranges 1-50 μg mL-1 for AML and ATV in the HPLC method and in the range of 3-50 and 4-50 μg mL-1 for AML and ATV, respectively, in the CE method. The proposed methods were validated according to ICH guidelines. The methods were successfully applied to estimation of AML and ATV in combined tablets.


2003 ◽  
Vol 48 ◽  
pp. 25-30 ◽  
Author(s):  
Svetlana Kulevanova ◽  
Marina Stefova ◽  
Tatjana Kadifkova Panovska ◽  
Trajce Stafilov

A new and rapid HPLC method for identification and determination of myricetin, quercetin, kaempferol and total flavonoids in ten herbal drugs of Macedonian origin is presented. Preparation of samples (Uvae ursi folim, Pruni spinosae flos, Sambuci flos, Betulae folim, Primulae flos, Herniariae herba, Centaurii herba, Tiliae flos, Robiniae pseudoacaciae flos, Bursae pastoris herba) included hydrolysis of glycosides and extraction of total aglycones with ethyl acetate. HPLC analysis with UV-diode array detection was carried out on RP C18 column, using 5% acetic acid and acetonitrile in agradient elution mode and column temperature of 30 o C. The monitoring of the elution is performed in the whole UV-range and the acquisition of data for quantitative analysis at 367 nm. Screening of the extracts showed presence of quercetin in nine, kaempferol in seven and myricetin in only one sample. The quantitative analysis showed that the content of quercetin ranged from 0.026-0.506 % (m/m), while for kaempferol it was from traces to 1.246 %. Uvaeursi folium and Pruni spinosae flos were rich in content of quercetin (0.482 % and 0.506 %, respectively), while Pruni spinosae flos and Robiniae pseudoaccaciae flos contained the highest amounts of kaempferol (1.246 % and 0.892 %, respectively). Myricetin was identified and determined only in Betulae folium (0.102 %). The content of total flavonoids in the investigated samples expressed in terms of quercetin ranged from 0.040 to 1.680 %. The proposed HPLC method is convenient for use in routine analysis of myricetin, quercetin and kaempferol, as well as for estimation of total flavonoids content in herbal drugs.


Sign in / Sign up

Export Citation Format

Share Document