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1

Analytical quality by design approach for the control of potentially counterfeit chloroquine with some NSAIDS using HPLC with fluorescence detection in pharmaceutical preparation and breast milk

Hassan Said A., Ibrahim Noha, Elzanfaly Eman S., El Gendy Ahmed E.

Acta Chromatographica

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2021

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Vol. 33, no. 3

234--244

EN

Chloroquine phosphate (CQ) the antimalarial drug and suggested to treat the pandemic disease coronavirus (COVID-19) is often adulterated with some of the non-steroidal anti-inflammatory drugs (NSAIDs) such as paracetamol, aspirin (ASP), or both. The purpose of this study is to detect such counterfeited drugs, using a reversed phase high pressure liquid chromatography (RP-HPLC) method with fluorescence detection. Analysis was divided into three phases. In the first phase, a Plackett-Burman design (PBD) was used to screen five independent factors, namely, buffer pH, buffer concentration (mM), acetonitrile content (%), flow rate (mL/min) and triethylamine (TEA) content in the buffer preparation (%). The selected dependent variables were (resolution, symmetry of peaks and run time). The objective of the second phase was to optimize the method performance using Box-Behnken design (BBD) and desirability function for multiple response optimization to obtain the best chromatographic performance with the shortest run time. Optimal chromatographic separation was achieved on a YMC-pack pro C18 ODS-A column (15 cm × 4.6 mm, 5 µm) at room temperature The optimum mobile phase consisted of acetonitrile and 5 mM sodium dihydrogen phosphate buffer containing 0.5% triethyamine (30:70, v/v) with the pH adjusted to 3.5 using an orthophosphoric acid solution. The flow rate was maintained at 1 mL/min, and the detection was performed with a fluorescence detector fixed at 380 nm(λemission) after excitation at 335 nm(λexcitation). The third phase was method validation according to ICH guidelines, providing to be specific, precise, accurate, and robust. The method is linear over a range of 0.4–8 µg/mL for chloroquine and ASP, while for paracetamol it is linear over 16–48 µg/mL. The developed RP-HPLC method was used for quantitation of the three drugs in chloroquine dosage form samples. The method shows a great tendency in the classification between the genuine chloroquine and the adulterated ones in pharmaceutical preparations and breast milk.

2

Determination of quinolonones in food of animal origin by liquid chromatography coupled with fluorescence and mass spectrometric detection

Stoilova N., Surleva A., Stoev G.

Acta Chromatographica

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2014

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Vol. 26, no. 4

599--614

EN

High-performance liquid chromatography coupled with fluorescence (HPLC-FD) and tandem mass spectrometric detection (LC-MS/MS) was studied as a versatile tool for fast and reliable determination of nine regulated quinolones in food of animal origin (Council Regulation 2377/90/ECC). The sample pre-treatment protocol includes double step extraction with acetonitrile followed by solid phase extraction (SPE) cleanup on hydrophobic-lipophilic balance (HLB) cartridge. The separation of quinolones in HPLC-FD determination was performed on C18 Zorbax column with a gradient mixture of aqueous formic acid, methanol, and acetonitrile. A multi-wavelength excitation/emission program was used for sensitive quinolones detection. The separation efficiency of newly available chromatographic columns: Gemini C18 and Synergi Polar RP (fully porous particles), as well as Kinetex PFP and Poroshell 120 EC-C18 (core-shell particles), was studied in liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) analysis. Appropriate gradient elution program was designed for each column. Multiple reaction monitoring was used for selective determination of each quinolone. LC-MS/MS allowed quinolones determination in less than 5 min. Both methods showed detection limits below maximum residue limits for quinolones residues in food commodities.

3

Mobile phone as a fluorescence reader

Shahin H., Walczak R.

Optica Applicata

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2013

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Vol. 43, nr 3

413--420

EN

A new achievement of mobile phone application for fluorometry to identify cocaine concentration using samples made of tested person sweat implementing special designed software has been presented in this paper. Accessibility is one of most dominant features of this method since the main important part is a mobile phone which can be found and used vastly. Reliability of data collected using this technique is strong enough to compete with past time consuming and expensive devices and equipment. The results enable to have a close and precise observation about the amount of cocaine concentration, the same as reference device outputs.

4

Determination of icariin in bushenqiangshen capsule in high-performance liquid chromatography with fluorescence detection by precolumn chelation with aluminum

Yang G. J, Lv L.

Acta Chromatographica

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2012

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Vol. 24, no. 2

229--239

EN

A simple and sensitive method of high-performance liquid chromatography with fluorescence detection (HPLC-FLD) was developed for the determination of icariin in capsules by precolumn chelation with aluminum. In order to obtain a stable fluorescence signal, the reaction conditions of the fluorescent chelation complex between icariin and aluminum were investigated in detail. Chromatography was carried out on an Agilent Zorbax Extend C18 column (150 mm × 4.6 mm, 5.0 μm) using methanol as mobile phase at a flow rate of 1.0 mL min-1. The excitation and emission wavelengths were set at 430 and 480 nm, respectively. At optimum conditions, the calibration curve was linear in the concentration range from 0.010 to 100.0 μg mL-1 with the limit of detection of 3.5 ng mL-1 (S/N = 3). A comprehensive method was validated for precision and accuracy. The method described here has been successfully applied for the determination of the icariin content in a capsule with satisfactory results.

5

Image sensor-based fluorescence detection for lab-on-a-chip

Walczak R.

Elektronika : konstrukcje, technologie, zastosowania

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2010

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Vol. 51, nr 11

33-36

PL

W artykule przedstawiono krótką dyskusję na temat detekcji fluorescencji w mikrosystemach typu lab-on-a-chip. Przedstawiono nowe rozwiązanie techniczne bazujące na czujniku obrazowym współpracującym ze specjalizowanych oprogramowaniem autorskim. Przedstawiono przykład wykorzystujący opracowany układ detekcji fluorescencji w przenośnym urządzeniu do detekcji patogenów żywności wykorzystujący analizę DNA bakterii.

EN

In the paper a brief discussion on fluorescence detection in lab-on-a-chip is carried out. A novel, low-cost image sensor-based detection instrumentation co-working with a "clever" software is described. An example of application of the novel method in a portable device for detection of food pathogens by DNA analyze is presented.

6

Rapid analysis of loratadine in human serum by high-performance liquid chromatography with fluorescence detection

Plenis A., Konieczna L., Olędzka I, Kowalski P.

Acta Chromatographica

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2010

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Vol. 22, no. 1

69--79

EN

A simple and rapid high-performance liquid chromatographic method with fluorescence detection for analysis of loratadine (LOR) in small volumes of human serum has been developed and validated. After solid-phase extraction (SPE), with thioridazine hydrochloride as internal standard, chromatographic separation was performed on a C 18 analytical column with 70:30 ( v / v ) acetonitrile-water, adjusted to pH 2.7 with orthophosphoric acid as mobile phase at a flow-rate of 1 min mL -1. The column was maintained at 28°C. Fluorescence detection was performed at excitation and emission wavelengths of 265 of 454 nm, respectively. The method was validated for accuracy, precision, selectivity, linearity, recovery, and stability. Absolute recovery of LOR was >93.0%. The limits of detection (LOD) and quantification (LOQ) were 0.07 and 0.2 ng mL -1,respectively. Linearity was confirmed in the range 0.2–30 ng mL -1 (correlation coefficient >0.9998). This HPLC method is selective, robust, and specific and would enable efficient analysis of large numbers of serum samples in support of pharmacokinetic, bioavailability, or bioequivalence studies after therapeutic doses of LOR.

7

Direct Liquid Chromatography with Photodiode and Fluorescence Detection for Simultaneous Quantification of Gonadotropin-Releasing Hormone (GnRH), Its Complex with Cu2+, and Catabolites

Michaluk A., Gajewska A., Kulon K., Kozłowski H., Kochman K., Kowalczyk J., Czauderna M.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 3

383-390

EN

Gonadotropin-releasing hormone (GnRH) and its complex with Cu2+(Cu-GnRH) were separated on a Nova Pak C18 column (4 m, 150 3.9 mm I.D., Wa ters). Analyses of underivatized GnRH and Cu-GnRH were per formed by a gradient elution program (HPLC method I), UV detection at 280 nm and fluorescence detection (gammexcitation = 280 nm/gammaemis sion = 360 nm). The mobile phases used were: acetonitrile with 0.08% trichloroacetic acid (w/w) and water with 0.1% trichloroacetic acid (w/w). Elutions were carried out in a binary gradient mode with a flow-rate of 1 mL/min and column temperature of 28°C. The proposed gradient elution program with UV and fluorescence detection allowed satisfactory fraction ation of GnRH (at 31.5 plus minus 0.2 min) from Cu-GnRH (at 30.3 plus-minus 0.2 min) and endogenous species present in samples of cytosol and subcellular organelles from the hypothalamus. The proposed reversed-phase HPLC method I with fluorescence detection provides a more sensitive analytical tool for routine and simultaneous quantification of GnRH, Cu-GnRH and their enzymatic degradation products (catabolites) in all biological samples as compared with HPLC method I with UV detection. To avoid problems due to overlap ping peaks corresponding to GnRH, Cu-GnRH, and the respective enzymatic degradation products in samples of cytosol and subcellular organelles from the hypothalamus, we propose a very shallow binary gradient elution program (method I). The separation efficiency of GnRH and Cu-GnRH peaks in standards and biological samples was assessed based on purity analysis of UV spectra (250-300 nm) and on the values of ratios of the fluorescence response to UV response at 280 nm. Our second reversed-phase liquid chromatographic method (HPLC method II) with pre-column derivatization of aminoacids in catabolites of GnRH and Cu-GnRH enabled investigations of the degradation pattern as well as of the yield of enzymatic degradation of GnRH and its Complex with Cu2+ in pituitary cytosol and sub-cellular organelles.

8

Simple HPLC analysis of tocopherols and cholesterol from specimens of animal origin

Czauderna M., Kowalczyk J., Niedźwiedzka K. M.

Chemia Analityczna

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2009

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Vol. 54, No. 2

203-214

EN

An improved saponification method followed by original isocratic high-performance liquid chromatography (HPLC) with photodiode detection (996 PAD, Waters) and/or fluorescence detection (474 Waters) for simultaneous analysis of cholesterol (CHOL) and δ-, α y-tocopherols (δ-T, α-T and y-T; forms of vitamin E) has been described. The method involved direct saponification of sample solutions flushed with a stream of argon, in the presence of vitamin C, followed by isocratic liquid chromatographic elution (Nova Pak C18column, 4 μm, 300 x 3.9 mm, I.D., Waters) and photodiode detection (UV) at 205 nmand/or fluorescence monitoring (&lambdaex/&lambdaem; = 290/327 nm). Reversed-phase HPLC analyses have revealed that the optimum separation of CHOL and tocopherol from endogenous substances in biological samples can be obtained using the mobile phase containing 17% propan-2-ol and 83% of acetonitrile (v/v) at the flow rate of 1.5 mLmin-1. Applying isocratic elution with UV monitoring at 205 nm and fluorescence detection, 8-T, a-T, y-T and CHOL were eluted after 6.19 š 0.09, 7.01 š 0.08, 7.79 š 0.08 and 14.7 š 0.2 min, respectively.UV detection at 205 nm assured better detector responses for all tocopherols compared to other wavelengths. Detailed investigations have proven that alkaline saponification at 80°C for 15 min followed by isocratic chromatographic elution and UV and fluorescence detection enable simple and satisfactory simultaneous analysis of CHOL and &delta-; α y-tocopherols in specimens of animal origin.

PL

Opisano poprawioną metodę jednoczesnego oznaczania cholesterolu oraz 5-, a- i y-tokoferoli (trzy formy witaminy E). Metoda polega na zmydlaniu próbki i następnie zastosowaniu oryginalnej, izokratycznej, wysokosprawnej chromatografii cieczowej z detekcją wykorzystującą fotodiodę (996 PAD Waters) oraz zdetekcjąfluorescencyjną (474 Waters). Zmydlanie próbki prowadzono w roztworze mieszanym strumieniem argonu w obecności witaminy C. Inne warunki onaczanie: kolumna Nova Pak C18 4 μm, 300 x 3,9 mm I.D., Waters; detekcja w nadfiolecie - 205 nm; fluorescencja:λex/ λem= 290/327 nm. W układzie odwróconych faz najlepsze rozdzielenie otrzymano w przypadku fazy ruchomej o składzie objętościowym: propan-2-ol — 17% i acetonitryl - 83%. Po rozdzieleniu piki δ-, α- i y-tokoferoli oraz chloroform pojawiły się w czasach: 6,19 š 0,09, 7,01 š 0,08, 7,79 š 0,08 and 14,7 š 0,2min. Najlepszą detekcję UV, dla wszystkich tokoferoli, otrzymano przy długości fali 205 nm. Stwierdzono również, że ługowanie alkaliczne w 80°C przez 15 min umożliwia prostą, jednoczesną chromatograficzną analizę tokoferoli w próbkach pochodzenia zwierzęcego.

9

Optimisation od densitometric fluorescence detection conditions of selected carcinogenic compounds in planar chromatography

Tyrpień K., Szumska-Kostrzewska M., Dobosz C.

Chemia Analityczna

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2007

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Vol. 52, No. 5

749-756

EN

The aim of the presented research was to optimize fluorescence detection conditions for selected biological active organic compounds after their TLC separation using densito-metry. Application of fluorescence to a quantitative analysis of organic compounds requires measuring fluorescence vs. time dependence separately for each determined compound. In this paper, time changes

PL

Celem pracy była optymalizacja warunków pomiarów fluorescencj i wybranych aktywnych biologicznie związków organicznych. Badane związki rozdzielano za pomocąTLC z zastosowaniem densytometrii. Wykorzystanie metody fluorescencyjnej do analizy ilościowej związków organicznych wymaga prowadzenia pomiaru zmian fluorescencji w czasie, oddzielnie w przypadku każdego oznaczanego związku. W pracy przedstawiono wyniki takich pomiarów dla różnych grup związków o własnościach kancerogennych.

10

Fluorescence guided intraoperative detection of malignant gliomas

Kaskelyte D., Gadonas R., Smilgevicius V., Skauminas K., Gudinaviciene I., Didziapetriene J., Grazeliene G., Sukackaite A.

Acta Bio-Optica et Informatica Medica. Inżynieria Biomedyczna

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2004

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Vol. 10, nr 1-2

32-32

11

Validation of the assay of metoprolol in human plasma using liquid-liquid extraction and high performance liquid chromatography with fluorescence detection

Farca A., Tache F., Medvedovici A., David V.

Chemia Analityczna

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2003

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Vol. 48, No. 4

677-688

EN

Metoprolol was successfully assayed in human plasma samples. The sample preparation procedure was based upon liquid-liquid extraction, using propranolol as internal standard (I.S.). The HPLC procedure developed using a Merck Chromolith column was based on the ion pairing separation mechanism. Fluorescence detection (ex. 230 nm; em. 305 nm) provided an excellent detectability (the determined quantitation limit, LOQ was 7.5 ng ml/1). Both sample preparation and chromatographic procedure were validated and used in a single-dose comparative bioequivalence study carried out on thirteen healthy volunteers. The same column was used for the entire determination and no major alteration of the separation behaviour was observed.

PL

Oznaczano metoprolol w próbkach ludzkiej plazmy. W procedurze przygotowania próbek zastosowano ekstrakcję cieczową z propranololem jako wewnętrznym standardem. Rozdzielanie HPLC prowadzono na kolumnie Merck Chromolith wykorzystując mechanizm parowania jonowego oraz detekcję fluoroscencyjną . Uzyskano bardzo dobrą wykrywalność (LOQ - 7.5 ng L'1). Przeprowadzono walidację procedury przygotowania próbek oraz ich chromatograficznego oznaczania. Metodę zastosowano do badań porównawczych między trzynastoma zdrowymi wolontariuszami, którzy zażywali po jednej dawce lekarstwa. Tę samąkolunmę zastosowano do wszystkich oznaczeń i nie obserwowano żadnych istotnych zmian.