Poster Proceedings
DETERMINATION OF SALICIN CONTENT IN FOOD SUPPLEMENTS CONTAINING WILLOW BARK
Adina Căta1, Mariana N. Ştefănuţ1, Ioana M.C. Ienaşcu1,2
1 National Institute of Research and Development for Electrochemistry and Condensed Matter, Dr. Aurel Păunescu Podeanu 144, 300569, Timişoara, Romania
2“Vasile Goldiş” Western University of Arad, Faculty of Pharmacy, Liviu Rebreanu 86, 310045, Arad, Romania
e-mail: adina.cata@yahoo.com
Abstract
The medicinal properties of willow bark can be attributed to the presence of salicylic glycosides, mainly salicin and salicortin. Salicin is the metabolic precursor of salicylic acid and has a similar action in the human body. Preparations containing willow bark extract are popular herbal remedies and have been used for anti-inflammatory, anti-rheumatic, antipyretic, antihypertensive, analgesic, antiseptic and astringent properties but many of them are not chemically standardized. The aim of this work was to investigate the presence of salicin in some commercially available food supplements (willow bark for tea, capsules containing willow bark, capsules and tablets containing willow bark extract). Salicin content in six Salix supplements, was quantified through HPLC-DAD analysis. According to the information provided by the manufacturer, only for two of the selected food supplements there is specified the content of salicin. The presence of salicin was monitored at 266 nm. Prior to chromatographic analysis, all products were extracted with methanol for 2 hours under heating and stirring. The highest salicin content was identified in capsules of Salix alba extract from Rotta Natura.
Acknowledgements
This work is part of the project PN 19 22 03 01 / 2019 “Supramolecular inclusion complexes of some natural and synthetic compounds with applications in health”, carried out under NUCLEU Program funded by National Authority for Scientific Research (Romania).
References
[1] M. Shara, S.J. Stohs, Phytotherapy Research, 29 (2015) 1112.
[2] J.G. Mahdi, A.J. Mahdi, A.J. Mahdi, I.D. Bowen, Cell Proliferation, 39 (2006) 147.
[3] J.G. Mahdi, Journal of Saudi Chemical Society, 14 (2010), 317.
25th International Symposium on Analytical and Environmental Problems
SYNTHESIS OF IRON OXIDE (Fe2O3) BY HYDROTHERMAL DECOMPOSITION OF Fe-Na4EDTA COMPLEX AT TEMPERATURES BETWEEN 140 ºC AND 200 ºC
Marius Chirita1,*, Liviu Mocanu1
1National Institute for Research and Development in Electrochemistry and Condensed Matter, Timisoara, PlautiusAndronescu Str. No. 1, RO-300224, Timisoara, Romania
*Coresponding author:chirifiz@gmail.com
Continuing our previous studies [1,2], the present experimental procedure is focused on the hydrothermal decomposition of the Fe(II)-EDTA complex in the presence of urea at temperatures between 140ºC and 200ºC after 4 h of high pressure-temperature treatment time.
Fe2O3 particles with dimensions between 1 and 2 micrometers were obtained. The experiments were repeated in identical concentrations by progressive decreasing temperature from 200ºC to 140ºC 20 to 20 degrees. The molar concentrations were identical in all cases. It was found that the lowest temperature at which the hematite synthesis process takes place is 140ºC.
a) (b)
Figure 1: SEM Images of micrometric Fe2O3 (a) and EDAX spectrum (b)
In the EDAX spectrum of these samples, only iron and oxygen maxima can be seen, which unequivocally indicates that the final product is pure Fe2O3, without traces of S, Na, C, N which could have resulted from the precursor’s decomposition. The diffraction spectrum (not presented here) showed distinct maxima for hematite only.
Keywords: hematite, crystalline, micrometric.
References:
[1] M. Chirita, R. Banica, A. Ieta, A. Bucur, P. Sfirloaga, D. H. Ursu, and I. Grozescu,
“Highly Crystalline FeCO3 Microparticle Synthesis by Hydrothermal Decomposition of Fe-EDTA Complex.” American Institute of Physics Conf Proceedings, vol. 1262/2010: 124.
[2] M. Chirita, R. Banica, P. Sfarloaga, A. Ieta, I. Grozescu, “A short route of micrometric magnetite synthesis via Fe-EDTA thermal decomposition.” IEEE ConfProc 11-13 Oct. 2010, ISBN 978-1-4244-5781-6, pp. 391-394.
25th International Symposium on Analytical and Environmental Problems
HYDROTHERMAL SYNTHESIS OF THE MIXED-PHASES BASED ON Mn FOR LITHIUM ION BATTERY APPLICATION
Dabici Anamaria1, Ursu Daniel1, Vajda Melinda1, Miclau Marinela1*, Casut Cristian1, Albulescu Daiana1
1National Institute for Research and Development in Electrochemistry and Condensed Matter, 1 Plautius Andronescu Street, 300224 Timisoara, Romania
e-mail: marinela.miclau@gmail.com Abstract
Over the past few years, Li-ion batteries (LIBs) have been widely applied in mobile devices, electronic vehicles (EVs) and energy storage systems in our daily life [1,2]. The cathode material is a critical part in LIBs which determines the electrochemical properties.
Among this family, Mn-based layered cathode materials, considered as one of the most promising candidates in next-generation rechargeable batteries, have been attracting significant attention due to their extraordinarily high specific capacity of 280 mA h g-1, potential in improving the working voltage to 4.8 V and relatively high Li-ion diffusivity compared with LiFePO4 and LiMn2O4. Materials such as: Li1.2Ni0.13Co0.13Mn0.54O2 and Li1.2Mn0.56Ni0.16Co0.08O2 have been investigated intensively, however, the progress of the commercialization has been slow due to voltage fade, insufficient rate capability and structural degradation during long-time cycling, which are considered as the bottlenecks for further promotion [5].
According to the literature reports, the layered Li2MnO3 belongs to the C2/m symmetry where Li and Mn ions occupy the octahedral interstices of a cubic close-packed oxygen lattice [6]. Forming composite phase of Li2MnO3 with other polymorphs of lithium metal oxides is also of great interest. For example, Li2MnO3–LiMO2 M = Mn, Co, Ni, Cr, etc.
etc. composite electrode materials were reported where the Li2MnO3 in the composite can stabilize the monoclinic structure of LiMO2 upon cycling [7].
In this paper, we report the successful hydrothermal synthesis of LiMnO2/Li2MnO3
obtained from hydrothermal method at 250 °C for 48 hours using 10mL H2O and Na2S208 as oxidant. The structure of products was determined by powder X-ray diffraction (XRD) PW 3040/60 X’Pert PRO using Cu-Kα radiation with (λ=1.5418Å), in the range 2θ = 10-80°, at room temperature (figure 1a). A Scanning Electron Microscope InspectS (SEM) was used to observe the morphology of synthesized nanocrystals (figure 1b). The diffuse reflectance spectra (DSR) was obtained using a Lambda 950 UV-Vis-NIR Spectrophotometer with 150 mm integrating sphere in the wavelength range of 300–800 nm.
Figure 1. a) X-ray diffraction patterns and b) SEM images of LiMnO2/Li2MnO3 obtained from hydrothermal method at 250 °C for 48 hours.
25th International Symposium on Analytical and Environmental Problems
Acknowledgements
This paper is supported by the Romanian Government under the project PN 19 22 01 03.
References
[1] B. Dunn and J. M. Tarascon, Science, 2011, 334, 928–935.
[2] B. Luo, B. Wang, X. Li, Y. Jia, M. Liang and L. Zhi, Adv. Mater., 2012, 24, 3538–3543.
[3] M. M. Thackeray, C. S. Johnson, J. T. Vaughey, N. Li and S. A. Hackney, J. Mater.
Chem., 2005, 15, 2257–2267.
[4] J. B. Goodenough and Y. Kim, Chem. Mater., 2010, 22, 587– 603.
[5] B. Xu, C. R. Fell, M. Chi and Y. S. Meng, Energy Environ. Sci., 2011, 4, 2223.
[6] P. J. Phillips, J. Bareno, Y. Li, D. P. Abraham and R. F. Klie, ˜ Adv. Energy Mater., 2015, 5, 1501252.
[7] M. M. Thackeray, C. S. Johnson, J. T. Vaughey, N. Li, and S. A. Hackney, J. Mater.
Chem., 2005, 15, 2257
25th International Symposium on Analytical and Environmental Problems
PHOTOCATALYTIC ACTIVITY OF METAL OXIDE NANOPARTICLES FOR REMOVAL OF THE HERBICIDE FLUROXYPYR FROM WATER Vesna Despotović1, Paula Sfirloaga2, Daniela Šojić Merkulov1, Biljana Abramović1
1University of Novi Sad Faculty of Sciences, Department of Chemistry, Biochemistry and Environmental Protection, Trg Dositeja Obradovića 3, 21000 Novi Sad, Serbia
2National Institute for Research and Development in Electrochemistry and Condensed Matter, Department of Condensed Matter, 1 Plautius Andronescu St., 300224 Timisoara,
Romania
e-mail: vesna.despotovic@dh.uns.ac.rs
Abstract
The photocatalytic materials absorb the photons having energy equals to or more than the band gap energy between the valence and conduction bands of the photocatalyst. The positive holes in the valence band either oxidize the water to produce hydroxyl radical or pollutant, whereas excited electrons reduce the adsorbed oxygen on the photocatalyst in the conduction band [1]. Till date a wide range of metal oxide/semiconductor-based nanomaterials have been explored for the photocatalytic degradation of harmful and toxic organic pollutants into the non-toxic products [2,3]. The aim of this work was to investigate removal of the herbicide fluroxypyr from double distilled water in the presence of novel TiO2, MgO and ZnO nanoparticles under UV and simulated solar irradiation. It was found that TiO2 photocatalyst showed higher photocatalytic activity for removal of fluroxypyr from water compared with MgO and ZnO. However, a major drawback of photocatalyst is that it has higher rate of recombination of photogenerated electron-hole pairs, which suppressed its catalytic potential [1,4]. Because of that it was investigated the photodegradation behaviour of fluroxypyr in aquatic systems using UV and simulated solar irradiation in the presence of TiO2/(NH4)2S208. The efficiency of elimination the herbicide from double distilled water was monitored by UFLC–DAD technique.
Acknowledgments
This work was supported by the Ministry of Education, Science and Technological Development of the Republic of Serbia (Project No. 172042).
References
[1] R. Gusain, K. Gupta, P. Joshi, O.P. Khatri, Adv. Colloid. Interf. Sci. 272 (2019) 102009.
[2] S. Ahmed, M.G. Rasul, R. Brown, M.A. Hashib, J. Environ. Manag. 92 (2011) 311.
[3] U.I. Gaya, A.H. Abdullah, J. Photochem. Photobiol. C Photchem. Rev. 9 (2008) 1.
[4] S. Ahmed, M.G. Rasul, W.N. Martens, R. Brown, M.A. Hashib, Desalination 261 (2010)
25th International Symposium on Analytical and Environmental Problems
ELECTROCHEMICAL BEHAVIOR OF QUERCETIN ON BORON-DOPED