HPLC−UV
Dotaz
Zobrazit nápovědu
Cílem práce bylo zavést a validovat analytickou metodu, která by umožnila detekovat koncentrace nabumetonu a kyseliny 6-methoxy-2-naftyloctové (6-MNA) po jednorázovém podání terapeutické dávky léčiva. Byly porovnány dvě metody stanovení pomocí HPLC s UV a hmotnostní detekcí. Při úpravě vzorku bylo optimálních výsledků dosaženo pomocí extrakce na pevné fázi (SPE). Výtěžnost se pohybovala okolo 84 % pro nabumeton a 86–90 % pro 6-MNA. HPLC separace analytů byla prováděna na reverzní C18 koloně. Limit UV detekce pro 6-MNA byl 50 nM, pro nabumeton 0,1 µM. Limit MS detekce pro 6-MNA činil 1 µM, pro nabumeton 0,5 µM. Přesnost metody pro stanovení nabumetonu se pohybovala v rozmezí 4,2–14,4 % při UV detekci a 4,6–8,5 % při MS detekci. Přesnost metody pro 6-MNA byla 2,4–12,5% při UV detekci a 2,1–9,4 % při MS detekci. Správnost metody pro stanovení nabumetonu se pohybovala v rozmezí 93,4–109,6 % při UV detekci a 86,2–107,9 % při MS detekci. Správnost metody pro 6-MNA byla 87,8–107,4 % při UV detekci a 86,3–106,4 % při MS detekci. Vhodnost metody byla ověřená na vzorcích pro stanovení farmakokinetiky léčiva u 24 zdravých dobrovolníků.
The study aimed to establish and validate an analytical method for the determination of nabumetone and 6-methoxy-2-naphthylacetic acid (6-MNA) in human plasma after a single therapeutic dose of the drug. Two methods based on HPLC with UV and MS detection were compared. Optimal results in sample preparation were achieved using solid phase extraction. The recovery reached approximately 84% and 86–90% for nabumetone and 6-MNA, respectively. A reverse C18 column was used for HPLC separation of the analytes. The limit of UV detection was 50 nM and 0.1 µM for 6-MNA and nabumetone, respectively. The limit of MS detection was 1 µM and 0.5 µM for 6-MNA and nabumetone, respectively. Precision ranged between 4.2–14.4% and 4.6–8.5% using UV and MS detection for nabumetone, respectively. The respective values for 6-MNA were 2.4–12.5% and 2.1–9.4%. Accuracy ranged between 93.4–109.6% in UV detection and 86.2–107.9% using UV and MS detection for nabumetone, respectively. The respective values for 6-MNA were 87.8–107.4% and 86.3–106.4%. The method was subsequently applied to determine the pharmacokinetic parameters of nabumetone and 6-MNA in a group of 24 healthy volunteers.
Je zde popsána metoda pro specifické stanovení kyseliny močové v lidském séru. Byla testována účinnost různých deproteinačních činidel. Výsledky získané proměřením 300 vzorků sér pomocí vysoce účinné kapalinové chromatografie byly porovnány s výsledky získanými rutinní enzymatickou metodou. Vzorky sér byly deproteinovány pomocí kyseliny chloristé a supernatanty byly analyzovány vysoce účinnou kapalinovou chromatografií na reverzní fázi. Pro separaci byla užita kolona MAG 1, 4,6 x 150 mm, Biospher PSI 200, 5 µm. Mobilní fází byla směs 5% metanolu v 25 mmol/l dihydrogenfosforečnanu sodného (v/v), pH 4,75. Analytické parametry metody jsou vyhovující: variační koeficienty přesnosti v sérii a mezi sériemi se pohybovaly pod 5 %. Výtěžnost, určená metodou standardních přídavků, se pohybovala v rozmezí 90,0–103,4 %. Mez stavitelnosti byla 10,0 µmol/l (3,3 pmol/nástřik). Výsledky získané chromatografickou metodou dobře korelovaly s výsledky získanými rutinní enzymatickou metodou, avšak chromatografická metoda poskytovala vyšší hodnoty, a to v závislosti na dané skupině pacientů. Zde prezentovaná metoda je vhodná pro analýzu těch vzorků, u nichž klasická enzymatická metoda poskytuje nespolehlivé výsledky.
A sensitive method for the specific determination of uric acid in human serum is described. The effectiveness of various protein precipitants was tested. Results from measurements by high-performance liquid chromatography on 300 serum samples were compared with an enzymatic method. Serum samples were deproteinized with perchloric acid and analyzed by reversed-phase high-performance liquid chromatography. For the separation, a reverse phase column MAG 1, 4.6 x 150 mm, Biospher PSI 200 C18, 5 µm, was used. The mobile phase consisted of 5% methanol in 25- mmol/L sodium dihydrogenphosphate (v/v), pH 4.75. The analytical performance of this method is satisfactory: the intra-assay and inter-assay coefficients of variation were below 5%. Quantitative recoveries of spiked serum samples were between 90.0 – 103.4%. The limit of quantification was 10.0 µmol/L (3.3 pmol/inject). Results obtained by chromatographic method correlated well with an enzymatic method, but gave at average higher values depending on a group of patients. Presented method is useful for the analysis of samples where the classical enzymatic method do not give reliable results.
- Klíčová slova
- porovnání metod,
- MeSH
- elektrochemické techniky metody přístrojové vybavení MeSH
- financování organizované MeSH
- kyselina močová analýza krev MeSH
- reprodukovatelnost výsledků MeSH
- spektrofotometrie ultrafialová metody přístrojové vybavení MeSH
- urikasa diagnostické užití MeSH
- vysokoúčinná kapalinová chromatografie metody přístrojové vybavení MeSH
Interest in the metabolism and physiological action of vitamin D is increased exponentially. The most important metabolites of vitamin D are 25-hydroxyvitamin and 1,25-dihydroxyvitamin D(3). The aim of the study was to develop a rapid and simple HPLC method for the measurement of 25-hydroxyvitamin D(3) in human plasma. A method for the measurement of 25-hydroxyvitamin D(3) using HPLC with UV detection and investigation into the extraction techniques with regard to stability and recovery are described. For the separation, RP column LiChroCart 125-4, Purospher RP-18e, 5 microm, was used. The mixture of methanol and deionized water (95:5 v/v) was used as mobile phase. The analytical performance of this method is satisfactory: the intra- and inter-assay coefficients of variation were below 10%. Quantitative recoveries from spiked plasma samples were between 92.0-103.2%. The LOD was 10 nmol/L. The preliminary reference range of 25-hydroxyvitamin D(3) in a group of blood donors is 62 +/- 26 nmol/L.
- MeSH
- dospělí MeSH
- extrakce na pevné fázi metody MeSH
- kalcifediol krev MeSH
- lidé MeSH
- referenční hodnoty MeSH
- senzitivita a specificita MeSH
- ultrafialové záření MeSH
- vysokoúčinná kapalinová chromatografie metody přístrojové vybavení MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- hodnotící studie MeSH
- práce podpořená grantem MeSH
A method for the measurement of ascorbic acid using HPLC with UV detection and investigation into the protein precipitation techniques with regard to stability and recovery are described. The effectiveness of various protein precipitants was tested. Stability of ascorbic acid samples for analysis was investigated over 10 h. Ascorbic acid samples extracted with metaphosphoric acid were stable on a cooled autosampler (4 degrees C) for at least 10 h (with a decline of 1.8% for ascorbic acid solution and 2.8% for plasma). Perchloric acid as protein precipitant for ascorbic acid was unsuitable (with a decline of 36.0% for ascorbic acid solution and 7.3% for plasma). Analytical performance of this method is satisfactory. The intra- and interassay coefficients of variation were 2.1% (n = 10) and 5.8% (n = 12), respectively. The calibration curve was linear with the tested range of 2.0-250.0 micromol/L. The recovery was 96.1% with CV = 4.8% (n = 6) and the LOD was 3 micromol/L. The preliminary reference ranges of ascorbic acid in a group of blood donors are 50.8 +/- 22.4 micromol/L. This assay is a highly sensitive and reproducible HPLC method for the determination of ascorbic acid in human plasma.
- MeSH
- antioxidancia chemie MeSH
- kalibrace MeSH
- kyselina askorbová chemie krev MeSH
- lidé MeSH
- referenční standardy MeSH
- reprodukovatelnost výsledků MeSH
- rozpouštědla MeSH
- senzitivita a specificita MeSH
- spektrofotometrie ultrafialová metody přístrojové vybavení MeSH
- vysokoúčinná kapalinová chromatografie metody přístrojové vybavení MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- kazuistiky MeSH
Efavirenz is an antiretroviral drug used in the treatment of HIV-positive patients. A simple, fast and sensitive high-performance liquid chromatography (HPLC) method was developed in order to determine efavirenz in three types of samples provided from pharmacokinetic studies. The analysis took 5min and was performed using a C18 analytical column (Discovery HS C18, 150×4.6mm, particle size of 5μm) in isocratic mode with a mobile phase containing acetonitrile and water (65:35, v/v), a flow rate of 1.6mLmin(-1), a sample volume of 10μL and UV detection at 245nm. Three different sample matrices (Opti-MEM medium, Krebs perfusion liquid and tissue lysate) and their treatment (dilution, SPE) were considered. The validated method was applied for the analysis of 805 real samples arising from in vitro transcellular transport assays and in vivo organ perfusion experiments in order to evaluate the interaction of efavirenz with ATP-dependent drug efflux transporters. The lack of interaction of efavirenz with ABCB1, ABCG2 and ABCC2 transporters as well as technical aspects of this analysis, including the adhesion of efavirenz to the plastic materials and the stability of the drug during different tissue lysis approaches are discussed.
- MeSH
- ABC transportér z rodiny G, člen 2 metabolismus MeSH
- acetonitrily chemie MeSH
- benzoxaziny chemie metabolismus MeSH
- biologický transport fyziologie MeSH
- buněčné linie MeSH
- buňky MDCK MeSH
- krysa rodu rattus MeSH
- P-glykoprotein metabolismus MeSH
- perfuze MeSH
- placenta chemie MeSH
- potkani Wistar MeSH
- proteiny spojené s mnohočetnou rezistencí k lékům metabolismus MeSH
- psi MeSH
- reprodukovatelnost výsledků MeSH
- stabilita léku MeSH
- těhotenství MeSH
- vysokoúčinná kapalinová chromatografie metody MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- psi MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
A simple, sensitive and quick HPLC method was developed for the determination of ketoprofen in cell culture media (EMEM, DMEM, RPMI). Separation was performed using a gradient on the C18 column with a mobile phase of acetonitrile and miliQ water acidified by 0.1 % (v/v) formic acid. The method was validated for parameters including linearity, accuracy, precision, limit of quantitation and limit of detection, as well as robustness. The response was found linear over the range of 3-100 μg/mL as demonstrated by the acquired value of correlation coefficient R2=0.9997. The described method is applicable for determination of various pharmacokinetic aspects of ketoprofen in vitro.
Oxidative stress has been proposed as one of the potential causes for infertility in men. Ascorbic acid and uric acid play important role in protection of spermatozoa against free radicals. A method for the simultaneous determination of ascorbic acid and uric acid in human seminal plasma using HPLC with UV detection and investigation their clinical significance as antioxidants protecting male germ cells against oxidative damage are described. Semen samples were obtained from consecutive male partners of couples presenting for a fertility evaluation. After liquefaction, the samples were centrifuged and the supernatants were diluted with dithiothreitol solution and after a filtration injected onto an analytical column. For the separation, a reverse-phase column MAG 1, 250 mm × 4.6 mm, Labiospher PSI 100 C18, 5 μm, was used. The mixture of ethanol and 25 mmol/L sodium dihydrogenphosphate (2.5:97.5, v/v), pH 4.70 was used as a mobile phase. Analytical performance of this method is satisfactory for both ascorbic acid and uric acid: the intra-assay and inter-assay coefficients of variation were below 10%. Quantitative recoveries from spiked seminal plasma were between 92.1 and 102.1%. We have found no significant differences in both ascorbic acid and uric acid concentration between the smokers and non-smokers (351.0 ± 237.9 μmol/L and 323.7 ± 99.5 μmol/L vs. 444.8 ± 245.5 μmol/L and 316.6 ± 108.9 μmol/L, p>0.05). This assay is a simple and reproducible HPLC method for the simultaneous measurement of ascorbic acid and uric acid in human seminal plasma.
- MeSH
- acetonitrily chemie MeSH
- chromatografie s reverzní fází MeSH
- dospělí MeSH
- kouření metabolismus MeSH
- kyselina askorbová analýza MeSH
- kyselina močová analýza MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- neparametrická statistika MeSH
- reprodukovatelnost výsledků MeSH
- spektrofotometrie ultrafialová MeSH
- sperma chemie MeSH
- vysokoúčinná kapalinová chromatografie metody MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
An HPLC method with UV and electrospray ionization - mass spectrometry (ESI-MS) detection was developed for the separation and determination of obeticholic acid (OBE) and its related compounds in development process and quality control. OBE and its related compounds were classified into three major group based on the mass spectra profiles: (A) those containing a hydroxyl group at position 3 and 7, (B) those containing a hydroxyl group and/or carbonyl group at position 3, hydrogen, ethyl or ethylidene group at position 6 and a hydroxyl group and/or carbonyl group at position 7, and (C) those containing carbonyl groups at position 3 and 7. ESI-MS ionization of OBE and its related compounds often produced intense adduct ions [M+H+98]+ and/or [M+H+196]+ that were identified as the adduct ions of phosphoric acid ([M+H+H3PO4]+ and [M+H+2H3PO4]+) originating from the mobile phase. The separation on HPLC system was accomplished using stationary phase based on XSelect CSH C18 (3.0×150mm×2.5μm) and a linear gradient elution using acetonitrile and 0.05% of o-phosphoric acid. The condition of chromatographic system was set as follows: flow rate 0.7mL/min, temperature 45°C and UV detection at 192nm. The separation of the 19 compounds was finished in less than 18min (including equilibration time). The HPLC/UV method was partially validated according to International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) guidelines in terms of repeatability, selectivity, linearity and limit of quantification and detection.
- MeSH
- chemická frakcionace přístrojové vybavení metody MeSH
- farmaceutická chemie metody MeSH
- hmotnostní spektrometrie s elektrosprejovou ionizací přístrojové vybavení metody MeSH
- kontaminace léku prevence a kontrola MeSH
- kyselina chenodeoxycholová analogy a deriváty analýza chemie MeSH
- limita detekce MeSH
- příprava léků přístrojové vybavení metody MeSH
- reprodukovatelnost výsledků MeSH
- řízení kvality * MeSH
- senzitivita a specificita MeSH
- spektrofotometrie ultrafialová přístrojové vybavení metody MeSH
- vysokoúčinná kapalinová chromatografie přístrojové vybavení metody MeSH
- Publikační typ
- časopisecké články MeSH
- validační studie MeSH
