Wyniki wyszukiwania - Biblioteka Nauki

1

Reverse phase high performance liquid chromatographic method development based on ultravioletvisible detector for the analysis of 1-hydroxypyrene (PAH biomarker) in human urine

100%

Kamal A. , Gulfraz M. , Anwar M. A. , Malik R. N.

International Journal of Occupational Medicine and Environmental Health

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2015

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tom 28

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nr 2

399-403

EN

Objectives 1-hydroxypyrene is an important biomarker of exposure to polycyclic aromatic hydrocarbons (PAHs), which appears in the urine of exposed human subjects. In developing countries, where advanced instruments are not available, the importance of this biomarker demands convenient and sensitive methods for determination purposes. This study aimed at developing a methodology to quantify 1-hydroxypyrene (a biomarker of PAHs exposure) based on the UV-visible detector in the reverse phase high pressure liquid chromatography (HPLC). Material and Methods A 20 μl injection of sample was used for manual injection into the HPLC Shimadzu, equipped with the SPD-20 A UV-visible detector, the LC-20AT pump and the DGU-20A5 degasser. The C-18 column was used for the purpose of the analysis. Results The method showed a good linearity (the range: R² = 0.979–0.989), and high detectability up to the nmol level. The average retention was 6.37, with the accuracy of 2%, and the percentage of recovery remained 108%. The overall performance of this method was comparable (in terms of detection sensitivity) and relatively better than previously reported studies using the HPLC system equipped with the UV-detector. Conclusions This method is suitable and reliable for the detection/quantification of the 1-OHP in human urine samples, using the UV-detector, however, it is less sensitive as compared to the results of a florescence detector.

2

Characteristics of Collagen Preparations from Leather Wastes by the High Pressure Liquid Chromatography Method

84%

Gendaszewska D. , Lasoń-Rydel M. , Ławińska K. , Grzesiak E. , Pipiak P.

Fibres & Textiles in Eastern Europe

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2021

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tom Vol. 29, no. 5 (149)

75--79

EN

The raw trimming waste from the leather industry is considered potential hazardous waste as a consequence of the chrome tanned leather process. On the other hand, leather waste contains a large amount of precious protein – collagen, which has many uses. Nowadays, collagen preparations obtained from leather waste are available on the market. This paper presents a procedure for the determination of amino acids in five collagen preparations of animal origin. Recent improvements in HPLC-based methods for analysing amino acids have made it feasible to analyse different sample types accurately. In this study the 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) derivatization procedure was applied. The amino acid analysis indicated the presence of 18 amino acids (Asp, Ser, Glu, His, Gly, Arg, Thr, Ala, Pro, Cys, Tyr, Val, Lys, Met, Ile, Leu, Phe and Hyp) in the collagen samples. Glycine, alanine, proline and hydroxyproline were the most abundant amino acid, whereas the lowest contents corresponded to serine, tyrosine, valine and izoleucine. The analysis proposed can be used with confidence in collagen quality control to guarantee appropriate amino acid content.

PL

Niegarbowane odpady skórzane pochodzące z przemysłu garbarskiego są potencjalnym zagrożeniem dla środowiska naturalnego. Z drugiej jednak strony tego rodzaju odpady zawierają znaczące ilości cennego białka – kolagenu. Białko kolagenowe jest biopolimerem, który z uwagi na swoje właściwości znajduje zastosowanie w przemyśle spożywczym, kosmetycznym oraz w przemyśle biomedycznym. Obecnie na rynku dostępne są preparaty kolagenowe pozyskane z odpadów pochodzenia zwierzęcego. W pracy przedstawiono procedurę oznaczania aminokwasów w wybranych preparatach kolagenowych metodą wysokosprawnej chromatografii cieczowej i metodą spektrofotometryczną. We wszystkich próbkach oznaczono wysokie stężenia glicyny, alaniny, proliny i hydroksyproliny, a niewielkie ilości tyrozyny, seryny, waliny i izoleucyny. Zastosowana metoda chromatograficzna umożliwia szybkie i równoczesne oznaczenie 17 aminokwasów w badanych próbach. Opracowane w ramach pracy metody analityczne mogą być wykorzystane m.in. do szybkiej kontroli składu aminokwasowego kolagenu.

3

Terapeutyczne monitorowanie leków - co, kiedy, kto i gdzie?

67%

Solnica B.

Laboratorium - Przegląd Ogólnopolski

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2006

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tom nr 10

44--45

PL

Terapeutyczne monitorowanie leków (TML) można zdefiniować jako wykonywanie oznaczeń stężenia leków we krwi w celu tworzenia, realizacji i kontroli indywidualnie dobieranych, skutecznych bezpiecznych schematów dawkowania wybranych leków. Zadaniem TML jest zwiększenie skuteczności i bezpieczeństwa farmakoterapii oraz obniżenie jej globalnych kosztów. Leki, których stężenie jest monitorowane, muszą spełniać szereg kryteriów uzasadniających przydatność ich terapeutycznego monitorowania , takich jak: potwierdzony związek stężenia leku we krwi z efektem farmakologicznym, niski wskaźnik terapeutyczny, zmienność farmakokinetyki i charakterystyka działań ubocznych. Racjonalne stosowanie TML wymaga przestrzegania wskazań klinicznych do jego podejmowania, takich jak: brak oczekiwanego efektu leczniczego, podejrzenie działań toksycznych, schorzenia wątroby lub nerek i interakcje leków.

EN

Therapeutic Drug Monitoring (TDM) can be defined as performing of serum drug assays to create, apply and control the individualized, effective and safe dosage schedules of selected drugs. The aims of TDM are increased efficacy and safety of drug treatment and decrease in its global costs. Drug which concentrations are monitored have to meet several criteria substantiating the usefulness of TDM, such as proven relationship between blood drug concentrations and the pharmacological effect, low therapeutic index, variability of pharmacokinetics and characteristics of side effects. The rational use of TDM requires adherence to clinical indications, such as lack of expected therapeutic effect, suspected drug toxicity, diseases of liver or kidneys a drug interactions.

4

Incidence of fumonisins, moniliformin and Fusarium species in poultry feed mixtures from Slovakia

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Labuda R. , Parich A. , Vekiru E. , Tancinova D.

Annals of Agricultural and Environmental Medicine

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2005

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tom 12

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nr 1

EN

A total of 50 samples of poultry feed mixtures of Slovak origin were analysed for fumonisin B1 and B2 (FB1, FB2) and moniliformin (MON) using SAX-clean up procedure being detected by high pressure liquid chromatography with mass spectrometry (HPLC-MS) and diode array detection (HPLC-DAD), respectively. The samples were also simultaneously investigated for Fusarium species occurrence, and for the capability of Fusarium isolates recovered to produce FB1 and MON in vitro. FB1 was detected in 49 samples (98%) in concentrations ranging from 43 to 798 µg.kg-1, and FB2 in 42 samples (84%) in concentrations ranging from 26 to 362 µg.kg-1. MON was detected in 26 samples (52%) in concentrations that ranged from 42 to 1,214 µg.kg-1. Only two Fusarium populations were encountered, namely F. proliferatum and F. subglutinans, of which the former was the most dominant and frequent. All 86 F. proliferatum isolates tested for FB1-production ability proved to be producers of the toxin although none of them produced MON. On the contrary, MON production was observed in a half out of 16 F. subglutinans isolates tested, yet no FB1 production was detected in this case. Despite the limited number of samples investigated during this study, it is obvious that poultry feed mixtures may represent a risk from a toxicological point of view and should be regarded as a potential source of the Fusarium mycotoxins in central Europe. This is the first reported study dealing with fumonisin and moniliformin contamination of poultry feeds from Slovakia.

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The effect of hexadecaprenol on molecular organisation and transport properties of model membranes

67%

Janas T. , Nowotarski K. , Gruszecki W. I. , Janas T.

Acta Biochimica Polonica

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2000

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tom 47

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nr 3

EN

The Langmuir monolayer technique and voltammetric analysis were used to investigate the properties of model lipid membranes prepared from dioleoylphosphatidylcholine (DOPC), hexadecaprenol (C80), and their mixtures. Surface pressure- molecular area isotherms, current-voltage characteristics, and membrane conductance-temperature were measured. Molecular area isobars, specific molecular areas, excess free energy of mixing, collapse pressure and collapse area were determined for lipid monolayers. Membrane conductance, activation energy of ion migration across the membrane, and membrane permeability coefficient for chloride ions were determined for lipid bilayers. Hexadecaprenol decreases the activation energy and increases membrane conductance and membrane permeability coefficient. The results of monolayer and bilayer investigations show that some electrical, transport and packing properties of lipid membranes change under the influence of hexadecaprenol. The results indicate that hexadecaprenol modulates the molecular organisation of the membrane and that the specific molecular area of polyprenol molecules depends on the relative concentration of polyprenols in membranes. We suggest that hexadecaprenol modifies lipid membranes by the formation of fluid microdomains. The results also indicate that electrical transmembrane potential can accelerate the formation of pores in lipid bilayers modified by long chain polyprenols.

6

Obraz skazen pozostalosciami pestycydow upraw rolnych i gleb w Polsce w latach 1991-1995

59%

Dabrowski J. , Gasior J. , Janda T. , Krause A. , Morzycka B. , Murawska M. , Sadlo S. , Barylska E. , Gierschendorf Z. , Giza I. , Langowska B. , Martinek B. , Michel M.

Progress in Plant Protection

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1996

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tom 36

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nr 1

57-76

7

Zastosowanie techniki HPLC do oznaczania aspartamu i acesulfamu-K w przetworach owocowych

59%

Szymczyk K. , Czerwiecki L.

Roczniki Państwowego Zakładu Higieny

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1995

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tom 46

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nr 4

373-381

PL

Adoptowano metodę oznaczania środków słodzących - acesulfamu K i aspartamu w niskokalorycznych, owocowo-warzywnych sokach przecierowych. Próbki badanych przetworów odbiałczano roztworami Carreza i po przesączeniu analizowano za pomocą techniki chromatografii cieczowej wysokociśnieniowej (HPLC) w fazach odwróconych.

EN

A liquid chromatographic method for the determination of the intense sweeteners - aspartame and acesulfam-K in fruit and vegetable nectars was described. Samples were extracted with water, then clarified with Carrez solutions. An aliquot of the extract was analyzed on C-18 reverse-phase column with UV detection. Mean recoveries ranged from 95,9 to 101,8%. The method is suitable for routine determinations of both sweeteners.