Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "spectrophotometry" wg kryterium: Temat


Wyświetlanie 1-3 z 3
Tytuł:
DETERMINATION OF FLUOXETINE HYDROCHLORIDE VIA ION PAIR COMPLEXATION WITH ALIZARIN RED S
Autorzy:
Clementina, Constantinescu I.
Alexandra, Neagu F.
Valentina, Uivarosi
Powiązania:
https://bibliotekanauki.pl/articles/895425.pdf
Data publikacji:
2018-12-31
Wydawca:
Polskie Towarzystwo Farmaceutyczne
Tematy:
spectrophotometry
Alizarin Red S
fluoxetine hydrochloride
ion pair
fluorimetry
Opis:
Two UV-Vis spectrophotometric methods and one fluorimetric method have been developed for the quantitative determination of fluoxetine hydrochloride in bulk and pharmaceutical formulations. These methods are based on the ion pair complex formation between alizarin red S and fluoxetine hydrochloride. In the first method (method A), the yellow-coloured complex obtained in acidic medium was extracted with chloroform, and the absorbance of chloroformic solution was measured at 425 nm. Beer’s law limits (9.5 – 48 µg/mL), the molar absorptivity (5256 L · mol-1· cm-1), and the complex composition (1:1) were determined. In the second method (method B), the yellow complex fluoxetine – alizarin red S extracted in chloroform was broken in alkaline medium, and the absorbance of the resulting violet-coloured free dye was measured at 524 nm. A linear relationship was observed in the range 9.0 – 54 µg/mL. In the third method (method C) the fluorescence intensity of the fluoxetine – alizarin red S complex, obtained in the same manner as for method A, was measured at 594 nm after excitation at 425 nm. The fluorescence intensity was proportional to the drug concentration in the linear range of 2.7-10.2 µg/mL. The limits of detection and quantification have also been calculated. Furthermore, the proposed methods have been successfully applied for the assay of the drug in pharmaceutical dosage forms.
Źródło:
Acta Poloniae Pharmaceutica - Drug Research; 2018, 75, 6; 1293-1303
0001-6837
2353-5288
Pojawia się w:
Acta Poloniae Pharmaceutica - Drug Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Free radical formation in salicylic acid and heating parameters – application of EPR, UV-Vis, TGA and colorimetry examination to optimize thermal sterilization
Autorzy:
Ramos, Paweł
Pilawa, Barbara
Powiązania:
https://bibliotekanauki.pl/articles/895669.pdf
Data publikacji:
2020-06-29
Wydawca:
Polskie Towarzystwo Farmaceutyczne
Tematy:
free radicals
EPR spectroscopy
salicylic acid
UV-Vis spectrophotometry
thermogravimetry
thermal sterilization
Opis:
Salicylic acid heated at different temperatures and times was examined by an X-band (9.3 GHz) EPR spectroscopy, UV-Vis spectrophotometry, TGA and colorimetry test to optimize its thermal sterilization process. Free radical formation (~1018 spin/g) during thermal sterilization of salicylic acid according to the pharmaceutical norms at temperature 120oC and time of 120 minutes was compared with those for heating at the new tested temperatures and times: 130oC and 60 minutes, and 140oC and 30 minutes. It was obtained that the relatively lower free radical concentrations characterized salicylic acid heated at temperatures (times): 120oC (120 minutes), and 130oC (60 minutes), than at temperature (time) 140oC (30 minutes). So treatment at temperature 120oC during 120 minutes, and temperature 130oC during 60 minutes, were recommended as the optimal for thermal sterilization of salicylic acid. Salicylic acid should not be sterilized at temperature 140oC during 30 minutes, because of the highest free radical formation. Free radical systems of thermally treated salicylic acid revealed complex character. Fast spin-lattice relaxation processes existed in heated salicylic acid. Strong dipolar interactions characterized all the heated salicylic acid samples. EPR spectroscopy, UV-Vis spectrophotometry, thermogravimetry, and color measurement may be helpful besides microbiological analysis to optimize thermal sterilization conditions of salicylic acid.
Źródło:
Acta Poloniae Pharmaceutica - Drug Research; 2020, 77, 3; 431-441
0001-6837
2353-5288
Pojawia się w:
Acta Poloniae Pharmaceutica - Drug Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Can angiotensin-converting enzyme inhibitors interfere with the free radicals? Measurement of antioxidant capacity using DPPH radical reduction examined by UV-VIS method
Autorzy:
Ramos, Paweł
Juszczak, Anna
Szczołko, Wojciech
Pilawa, Barbara
Stanisz, Beata J.
Powiązania:
https://bibliotekanauki.pl/articles/895342.pdf
Data publikacji:
2019-04-30
Wydawca:
Polskie Towarzystwo Farmaceutyczne
Tematy:
free radicals
antioxidant
UV-Vis spectrophotometry
angiotensin-converting enzyme inhibitors (ACE-I)
Opis:
A negative impact of radicals on human’s health is responsible for growing research interest in antioxidant properties of substances, which protect organisms from the damaging influence of these reactive species. Angiotensin-converting enzyme inhibitors (ACE-I) are the most popular drugs used in cardiovascular diseases. There are a lot of clinical reports that ACE-I have antioxidant properties, due to the fact, that prolonged use improves conditions of patients with neurodegenerative disorders and slow inflammatory processes. The paper shows the antioxidant properties of a selected ACE-I: cilazapril, ramipril, imidapril, lisinopril, perindopril, and quinapril. Among numerous methods for antioxidant activity estimation, DPPH reduction is the most popular and commonly used one due to its ease, speed, sensitivity and the usage of stable radicals. UV-Vis spectrophotometry was used to examine interactions of chosen ACE-I with model-free radicals. Absorption of UV-Vis spectra of DPPH (reference), and DPPH interacting with the tested ACE-I were compared. For all tested ACE-I kinetics of their interaction with DPPH, up to 30 minutes, were obtained. The strongest interaction with DPPH was observed for imidapril and cilazapril and the lowest interaction for lisinopril. Studies have shown usefulness UV-Vis spectrophotometry for obtaining information on interactions of ACE-I with model-free radicals.
Źródło:
Acta Poloniae Pharmaceutica - Drug Research; 2019, 76, 2; 233-239
0001-6837
2353-5288
Pojawia się w:
Acta Poloniae Pharmaceutica - Drug Research
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-3 z 3

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies