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231.
Voltammetric behavior and determination of antidepressant drug paroxetine at carbon-based electrodes
Brycht Mariola Skrzypek Sławomira Karadas-Bakirhan Nurgul Smarzewska Sylwia Bozal-Palabiyik Burcin Ozkan Sibel A. Uslu Bengi 《Ionics》2015,21(8):2345-2354
Ionics - Simple, rapid, sensitive, and reproducible methods were developed for the assay of paroxetine in tablets. The electrooxidative behavior and determination of paroxetine on boron-doped... 相似文献
232.
Semra Tan Sylwia Walus Jöns Hilborn Torbjörn Gustafsson Daniel Brandell 《Electrochemistry communications》2010,12(11):1498-1500
This paper presents a novel thin-film electrolyte of a 2:1 blend of polyetheramine (glyceryl poly(oxypropylene)) and cross-linked oligomeric poly(propylene oxide) diacrylate with LiTFSI. The polyetheramine acts as a surfactant, and can thereby be applied as a conformal coating on complex surfaces—here demonstrated for porous LiFePO4 cathodes—making it useful for 3D-microbatteries. The poly(propylene oxide) diacrylate blends with the surfactant and is easily UV cross-linked, thereby ensuring good mechanical stability. Electrolytes, ~ 2 μm thick, were casted onto LiFePO4 cathodes and cycled against metallic lithium, displaying stable discharge capacities of ~ 8 mAh/g at room temperature and ~ 120 mAh/g at 60 °C. The electrolyte showed conductivities of 3.45 × 10? 6 and 5.80 × 10? 5 S cm? 1 at room temperature and 60 °C, respectively. 相似文献
233.
Alejandro Ibez Bozena Skupien-Rabian Urszula Jankowska Sylwia Kdracka-Krok Bartomiej Zajc Maciej Pabijan 《Molecules (Basel, Switzerland)》2022,27(7)
Proteins are ubiquitous macromolecules that display a vast repertoire of chemical and enzymatic functions, making them suitable candidates for chemosignals, used in intraspecific communication. Proteins are present in the skin gland secretions of vertebrates but their identity, and especially, their functions, remain largely unknown. Many lizard species possess femoral glands, i.e., epidermal organs primarily involved in the production and secretion of chemosignals, playing a pivotal role in mate choice and intrasexual communication. The lipophilic fraction of femoral glands has been well studied in lizards. In contrast, proteins have been the focus of only a handful of investigations. Here, we identify and describe inter-individual expression patterns and the functionality of proteins present in femoral glands of male sand lizards (Lacerta agilis) by applying mass spectrometry-based proteomics. Our results show that the total number of proteins varied substantially among individuals. None of the identified femoral gland proteins could be directly linked to chemical communication in lizards, although this result hinges on protein annotation in databases in which squamate semiochemicals are poorly represented. In contrast to our expectations, the proteins consistently expressed across individuals were related to the immune system, antioxidant activity and lipid metabolism as their main functions, showing that proteins in reptilian epidermal glands may have other functions besides chemical communication. Interestingly, we found expression of the Major Histocompatibility Complex (MHC) among the multiple and diverse biological processes enriched in FGs, tentatively supporting a previous hypothesis that MHC was coopted for semiochemical function in sand lizards, specifically in mate recognition. Our study shows that mass spectrometry-based proteomics are a powerful tool for characterizing and deciphering the role of proteins secreted by skin glands in non-model vertebrates. 相似文献
234.
Sylwia Studziska Szymon Bocian Anna Kilanowska Bogusaw Buszewski 《Molecules (Basel, Switzerland)》2022,27(5)
Oligonucleotides are used in many research areas. Thus, there is a need for their successful separation methods. Ion-exchange chromatography is the most popular separation technique, but it has limitations for these compounds. For this reason, new stationary phases are developed in order to increase separation selectivity. This study aimed to apply a series of dendrimer anion exchangers with various bonded layers to separate oligonucleotides by using different mobile phases to find conditions that allow sufficient separation. The number of anion-exchange layers, type of salt, and pH significantly impacted the oligonucleotide analysis. The developed chromatographic method was characterized by adequate selectivity for oligonucleotides differing in sequence length. It is essential to underline that the number of bonded layers appeared to have a significant influence, and the three layers appeared optimal. Based on our results, it may be concluded that the dendrimer stationary phases can be successfully used as an alternative to commonly applied packing materials in ion-exchange chromatography. 相似文献
235.
Piotr Mynarz Micha Jewginski Sylwia
liwiska Rafa Latajka Grzegorz Schroeder Pawe Kafarski 《Heteroatom Chemistry》2007,18(7):774-781
Recently, bisaminophosphonates found applications as therapeutic agents for curing bone disorders. When trying to relate the structures of substituted piperid‐1‐ylmethylenebisphosphonic with their biological properties, non‐typical findings that in 31P NMR spectra of 2‐methyl‐piperid‐1‐ylmethylenebisphosphonic and 2‐ethyl‐piperid‐1‐ylmethylenebisphosphonic acids, two separate singlets from each of the phosphonic groups were observed, while their analogues bearing substituent in position 3 exhibit only one signal. Their presence was explained by freezing of the molecular motions by strong hydrogen bonding between NH and P = O atoms. In this work, synthesis as well as spectroscopic and theoretical investigations of the tetraethyl esters of 2‐methyl‐piperid‐1‐ylmethylenebisphosphonic in its racemic and enatiomerically pure forms are reported. Their 31P NMR spectra revealed two sets of dublets, which indicate the presence of two non‐equivalent phosphorous atoms. More detailed NMR and theoretical studies indicated that the nonequivalent phosphorous signals in 31P NMR spectra may results from the absence of C2 symmetry of the molecule along with the presence of large ester groups blocking the internal molecular motion around C—N bond, and thus blocking the interchange of ring conformation. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:774–781, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20349 相似文献
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237.
Dorota Maciejewska Pawe? Ka?mierczak Jerzy ?abiński Irena Wolska Sylwia Popis 《Monatshefte für Chemie / Chemical Monthly》2006,84(5):1225-1240
The synthesis of four new 1,5-bis(4-amidinophenoxy)-3-oxapentane analogs is described. The structures of the obtained bis-amidines
and bis-nitriles in the solid state are evaluated on the basis of 13C CP/MAS NMR spectra and theoretical calculations at DFT level. A single crystal X-ray diffraction structure is presented
for 1,5-bis(4-amidinophenoxy)-3-oxapentane. A preliminary anticancer assay against three cell lines is also given. 相似文献
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239.
The problem of arbitrary decomposition of a graph G into closed trails i.e. a decomposition into closed trails of prescribed lengths summing up to the size of the graph G was first considered in the case of the complete graph G=Kn (for odd n) in connection with vertex-distinguishing coloring of the union of cycles.Next, the same problem was investigated for other families of graphs.In this paper we consider a more general problem: arbitrary decomposition of a graph into open and closed trails. Our results are based on and generalize known results on decomposition of a graph into closed trails. Our results also generalize some results concerning decomposition of a graph into open trails. We here emphasize that the known results on the closed case are basic ingredients for the proof of the open and closed case. 相似文献
240.
Edyta?C?drowska Marek?Pruszynski Agnieszka?Majkowska-Pilip Sylwia?M?czyńska-Wielgosz Frank?Bruchertseifer Alfred?Morgenstern Aleksander?BilewiczEmail author 《Journal of nanoparticle research》2018,20(3):83
The 225Ac radioisotope exhibits very attractive nuclear properties for application in radionuclide therapy. Unfortunately, the major challenge for radioconjugates labelled with 225Ac is that traditional chelating moieties are unable to sequester the radioactive daughters in the bioconjugate which is critical to minimize toxicity to healthy, non-targeted tissues. In the present work, we propose to apply TiO2 nanoparticles (NPs) as carrier for 225Ac and its decay products. The surface of TiO2 nanoparticles with 25 nm diameter was modified with Substance P (5-11), a peptide fragment which targets NK1 receptors on the glioma cells, through the silan-PEG-NHS linker. Nanoparticles functionalized with Substance P (5-11) were synthesized with high yield in a two-step procedure, and the products were characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS) and thermogravimetric analysis (TGA). The obtained results show that one TiO2-bioconjugate nanoparticle contains in average 80 peptide molecules on its surface. The synthesized TiO2-PEG-SP(5-11) conjugates were labelled with 225Ac by ion-exchange reaction on hydroxyl (OH) functional groups on the TiO2 surface. The labelled bioconjugates almost quantitatively retain 225Ac in phosphate-buffered saline (PBS), physiological salt and cerebrospinal fluid (CSF) for up to 10 days. The leaching of 221Fr, a first decay daughter of 225Ac, in an amount of 30% was observed only in CSF after 10 days. The synthesized 225Ac-TiO2-PEG-SP(5-11) has shown high cytotoxic effect in vitro in T98G glioma cells; therefore, it is a promising new radioconjugate for targeted radionuclide therapy of brain tumours. 相似文献