38 research outputs found
Functionalization of polymers and carbon nanomaterials with low molecular weight receptors
Wydział Chemii: Zakład Chemii SupramolekularnejKontrolowana, chemiczna funkcjonalizacja materiałów poprzez wprowadzanie do ich struktury określonych grup funkcyjnych umożliwia zmianę ich właściwości fizykochemicznych lub nadawanie im specjalnych zastosowań.
Celem naukowym mojej pracy jest opracowanie metody syntezy i otrzymanie nowych, funkcjonalnych materiałów węglowych i polimerów zawierających receptory molekularne. Układy te mają wykazywać zdolność selektywnego wiązania jonów i cząsteczek oraz wykazywać zdefiniowane właściwości.
W celu otrzymania nowych matryc dla techniki MALDI-MS, które nie generowałyby sygnałów na widmie mas w rejonie niskich mas cząsteczkowych, przeprowadziłem funkcjonalizację nanorurek węglowych poprzez przyłączenie do ich powierzchni kwasu sinapowego. Uzyskane w ten sposób materiały zastosowałem jako matryce w analizie MALDI-MS surfaktantów, kwasu foliowego oraz wankomycyny.
Przeprowadzenie funkcjonalizacji określonych polimerów wymagało ode mnie uzyskania receptorów, które jednocześnie będą selektywne wobec odpowiedniego analitu i reaktywne względem grup funkcyjnych obecnych w strukturze polimeru. Pierwszym celem funkcjonalizacji polimerów było uzyskanie materiałów zdolnych do tworzenia selektywnych oddziaływań z cukrami i diolami. Drugim celem funkcjonalizacji polimerów było uzyskanie materiałów zdolnych do adsorpcji kationów metali przejściowych.Controlled chemical functionalization of materials achieved by introduction of defined functional groups to their structure, permits endowing the materials with specific target properties.
The aim of my doctoral dissertation was to design a method for the synthesis and to synthesise new functionalized carbon materials and polymers, containing molecular receptors capable of selective binding ions or molecules and showing defined properties.
One of my tasks was to obtain new matrices to be employed for matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS), which would not generate signals in the mass spectra in the region of low molecular mass. I functionalized carbon nanotubes surface with sinapic. The materials obtained were applied as matrices in the MALDI-MS analyses of surfactants, folic acid and vancomycin.
In order to functionalize certain polymers, it was necessary to obtain receptors that would be selective towards a given analyte and reactive towards the functional groups present in the polymer structure. The first task was to obtain materials capable of selective interactions with sugars and diols. The second aim of polymer functionalization was to obtain materials capable of adsorption of transition metal cations
The 42nd Symposium Chromatographic Methods of Investigating Organic Compounds : Book of abstracts
The 42nd Symposium Chromatographic Methods of Investigating Organic Compounds : Book of abstracts. June 4-7, 2019, Szczyrk, Polan
EGDMA- and TRIM-Based Microparticles Imprinted with 5-Fluorouracil for Prolonged Drug Delivery
Imprinted materials possess designed cavities capable of forming selective interactions with molecules used in the imprinting process. In this work, we report the synthesis of 5-fluorouracil (5-FU)-imprinted microparticles and their application in prolonged drug delivery. The materials were synthesized using either ethylene glycol dimethacrylate (EGDMA) or trimethylolpropane trimethacrylate (TRIM) cross-linkers. For both types of polymers, methacrylic acid was used as a functional monomer, whereas 2-hydroxyethyl methacrylate was applied to increase the final materials’ hydrophilicity. Adsorption isotherms and adsorption kinetics were investigated to characterize the interactions that occur between the materials and 5-FU. The microparticles synthesized using the TRIM cross-linker showed higher adsorption properties towards 5-FU than those with EGDMA. The release kinetics was highly dependent upon the cross-linker and pH of the release medium. The highest cumulative release was obtained for TRIM-based microparticles at pH 7.4. The IC50 values proved that 5-FU-loaded TRIM-based microparticles possess cytotoxic activity against HeLa cell lines similar to pure 5-FU, whereas their toxicity towards normal HDF cell lines was ca. three times lower than for 5-FU
Functional polymers as unique materials applied in selective adsorption
Functional polymers are increasingly being used as materials with a range of unique properties. Due to their structure and relatively high flexibility in a synthetic context, they are becoming highly relevant in a variety of applications. One of the numerous examples of the use of functional polymers is water treatment. Using the adsorption phenomenon, it is possible to remove or reduce the amount of harmful organic compounds and heavy metal ions in the water. This review provides information on both the synthesis methods and characterization of functional polymers in terms of their adsorption properties. Among others, this paper presents the results of research on functional polymers carried out by Professor Schroeder's research group. The research was mainly focused on the selective adsorption of dyes and heavy metal ions, which are significant water pollutants. The overall results show that the adsorption of the synthesized polymer materials is high influenced by parameters such as pH, temperature, contact time of the adsorbent with the adsorbate and the initial adsorbate concentration. In the case of the adsorption phenomenon, the Langmuir or Freundlich isotherm turned out to be the most appropriate model for the tested materials, while in the case of kinetic models, the highest R2 coefficient was usually obtained using the pseudo-second-order equation
The application of molecularly imprinted polymer-based materials and their influence on the development of supramolecular chemistry
Molecularly Imprinted Polymers (MIPs) are the group of polymers that possess an ability to selective recognize analytes or groups of analytes, which are similar by their structural construction. The recognizing ability, which is generated during the synthesis of material, is determined by various factors such as shape, size, and the presence of functional groups in the MIP cavity. This molecular recess is created as a result of removing the specific analyte from the inclusive complex (polymeranalyte). Thanks to the valuable properties of molecularly imprinted polymers, these materials are commonly used in various fields. The multitude of their applications results from their properties such as high physical stability to harsh chemical and physical conditions, straightforward preparation, remarkable robustness, excellent reusability, and relative low-cost synthesis. Due to the attractiveness of MIPs widely demonstrated in the literature, as well as the possibilities of their application in various fields, these materials also have gained the favor of Professor Grzegorz Schroeder’s research group, in which numerous scientific works devoted to the subject of their use have been published
HOMOLOGATION TESTS OF SINGLE-STAGE R02 REDUCER
This article presents the results of homologation tests of an LPG reducer. Due to the material requirements of the LPG reducer in this case, the R02 reducer, designed by the joint-stock company AC Spółka Akcyjna, is used. Test procedures, which must be carried out, are also presented and generally explained with specified conditions for conducting the processes. The advantages of using the R02 are also presented. The properties of aluminium alloy 226, which is the body of the reducer, are characterized and are divided into four groups: technological features/qualitative indications, physical properties, mechanical features and chemical composition. The whole article is summarized with appropriate conclusions
Poly(2-oxazoline)s as Stimuli-Responsive Materials for Biomedical Applications: Recent Developments of Polish Scientists
Poly(2-oxazoline)s are the synthetic polymers that are the products of the cationic ring-opening polymerization (CROP) of 2-oxazoline monomers. Due to their beneficial properties, from which biocompatibility, stealth behavior, high functionalization possibilities, low dispersity, stability, nonionic character, and solubility in water and organic solvents should be noted, they have found many applications and gained enormous interest from scientists. Additionally, with high versatility attainable through copolymerization or through post-polymerization modifications, this class of polymeric systems has been widely used as a polymeric platform for novel biomedical applications. The chemistry of polymers significant expanded into biomedical applications, in which polymeric networks can be successfully used in pharmaceutical development for tissue engineering, gene therapies, and also drug delivery systems. On the other hand, there is also a need to create ‘smart’ polymer biomaterials, responsive to the specified factor, that will be sensitive to various environmental stimuli. The commonly used stimuli-responsive biomedical materials are based mostly on temperature-, light-, magnetic-, electric-, and pH-responsive systems. Thus, creating selective and responsive materials that allow personalized treatment is in the interest of the scientific world. This review article focuses on recent discoveries by Polish scientists working in the field of stimuli-responsive poly(2-oxazoline)s, and their work is compared and contrasted with results reported by other world-renowned specialists
New gel-like polymers as selective weak-base anion exchangers.
A group of new anion exchangers, based on polyamine podands and of excellent ion-binding capacity, were synthesized. The materials were obtained in reactions between various poly(ethyleneamines) with glycidyl derivatives of cyclotetrasiloxane. The final polymeric, strongly cross-linked materials form gel-like solids. Their structures and interactions with anions adsorbed were studied by spectroscopic methods (CP-MAS NMR, FR-IR, UV-Vis). The sorption isotherms and kinetic parameters were determined for 29 anions. Materials studied show high ion capacity and selectivity towards some important anions, e.g., selenate(VI) or perrhenate
The Influence of TiO<sub>2</sub>–Lignin Hybrid Fillers in Low-Density Polyethylene Composites on Photocatalytic Performance and UV-Barrier Properties
The main objective of this study was to discover new packaging materials that could integrate one of the most expected properties, such as UV protection, with a self-cleaning ability defined as photocatalytic performance. Accordingly, new hybrid additives were used to transform LDPE films into materials with complex performance properties. In this study, titanium dioxide–lignin (TL) hybrid systems with a weight ratio of inorganic to organic precursors of 5-1, 1-1, and 1-5 were prepared using a mechanical method. The obtained materials and pristine components were characterized using measurement techniques and research methods, such as Fourier-transform infrared spectroscopy (FTIR), thermal stability analysis (TGA/DTG), measurement of the electrokinetic potential as a function of pH, scanning electron microscopy (SEM), and particle size distribution measurement. It was found that hydrogen bonds were formed between the organic and inorganic components, based on which the obtained systems were classified as class I hybrid materials. In the next step, inorganic–organic hybrid systems and pristine components were used as fillers for a low-density polyethylene (LDPE) composite, 5 and 10% by weight, in order to determine their impact on parameters such as tensile elongation at break. Polymer composites containing titanium dioxide in their matrix were then subjected to a test of photocatalytic properties, based on which it was found that all materials with TiO2 in their structure exhibit photocatalytic properties, whereby the best results were obtained for samples containing the TiO2–lignin hybrid system (1-1). The mechanical tests showed that the thin sheet films had a strong anisotropy due to chill-roll extrusion, ranging from 1.98 to 3.32. UV–Vis spectroscopy revealed four times higher light absorption for composites in which lignin was present than for pure LDPE, in the 250–450 nm range. On the other hand, the temperature at 5% and 30% weight loss revealed by TGA testing increased the highest performance for LDPE/TiO2 materials (by 20.4 °C and 8.7 °C, respectively)