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Nowe termowrażliwe powierzchnie polimerowe do hodowli i uwalniania komórek skóry

Oleszko-Torbus N., Utrata-Wesołek A., Wałach W., Dworak A., Trzebicka B.

Wiadomości Chemiczne

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2016

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[Z] 70, 11-12

803--818

EN

Covalent attachment of a thermoresponsive polymer to solid support leads to layers exhibiting temperature-dependent properties. Below the cloud point temperature (TCP) of the thermoresponsive polymer the layer is hydrophilic – it is hydrated and polymer chains adopt an expanded conformation. Above TCP, the polymer chains collapse due to dehydration and the surface becomes hydrophobic. This is a reversible process, lowering the temperature cause hydration and swelling of the layer. Such thermoresponsive layers can be obtained via reactions of entities present on the surface (e.g. functional groups, radicals etc.) with complementary functionalities in the polymer chains (grafting to) or with monomer subjected to polymerization (grafting from). Thermoresponsive layers may be used in many biomedical applications such as separation of molecules or cell sheet engineering. In this work, well-defined thermoresponsive (co)polymers of glycidol and ethyl glycidyl carbamate (mPGl), 2-ethyl and 2-nonyl-2-oxazoline (PENOx) as well as homopolymers of 2-isopropyl-2-oxazoline (PIPOx) were grafted to functionalized glass and silica substrates with the aim to obtain thermoresponsive layers for potential application in cell sheet engineering. Presence of polymers covalently bonded to substrates was confirmed by FT-IR and XPS studies. The polymer layers were 5-50 nm thick, depending on the molar mass and polymer concentration. Microscopic techniques indicated a smooth surface of mPGl layers, slightly rough texture of PENOx layers and fibrille-like fibers surface of PIPOx layers. Ellipsometry and contact angle studies revealed the response of layers to temperature changes. Biocompatibility of layers with dermal fibroblasts was confirmed by toxicity tests. Thermoresponsive surfaces were employed as substrates for skin cell culture and harvesting. Fibroblasts adhesion and proliferation on investigated surfaces was comparable with control sample. A confluent cell sheet was formed after 24 hours of culture. The influence of surface properties on cell adhesion and proliferation was examined. Detachment of cells from surfaces was controlled by variation of the temperature. An intact monolayer of cultured dermal fibroblasts was detached. No mechanical or enzymatic methods were required to harvest the cell sheets. Skin cell sheets, detached from thermoresponsive polymer layers may be applied in the cell sheet engineering that is highly desirable in tissue regeneration.

2

Termoczułe polimery gwieździste — synteza i właściwości

Dworak A., Trzebicka B., Kowalczuk A., Utrata-Wesołek A., Wałach W., Libera M., Kronek J.

Polimery

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2012

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T. 57, nr 6

441-448

PL

Zsyntezowano i scharakteryzowano dwa rodzaje (ko)polimerów gwieździstych: gwiazdy z ramionami zbudowanymi z poli(2-etylo-2-oksazoliny) i gwiazdy z ramionami z poli(eteru tert-butyloglicydylowego)-b-poliglicydolu. Zastosowane metody polimeryzacji żyjącej (kationowej i anionowej) umożliwiły kontrolę topologii otrzymywanych polimerów (liczby i długości ramion gwiazdy) i uzyskanie małej dyspersji mas molowych. Odpowiedni dobór parametrów strukturalnych (rodzaju rdzenia, ilości i długości ramion oraz, w wypadku gwiazd kopolimerowych, składu ramion) pozwolił na uzyskanie polimerów o różnych właściwościach: od rozpuszczalnych w wodzie po polimery termoczułe o różnych wartościach temperatury zmętnienia ich roztworów wodnych. Strukturę gwiazd skorelowano z ich termoczułością.

EN

Two kinds of termosensitive star polymers have been synthesized: stars with arms of poly(2-ethyl-2-oxazoline) and stars with arms of poly(tert-butyl glycidyl ether)-b-(polyglycidol). Under applied polymerization methods (living anionic and living cationic polymerization) the topology of the obtained polymers (number and length of star arms) have been controlled and low molar mass dispersities achieved. By the proper choice of structural parameters (nature of the core and the arms and, in the case of copolymer stars, the composition of the arms) polymers ranging from water soluble to termosensitive polymers of controlled cloud point temperature in water have been obtained. The star structure has been correlated with their thermosensitivity.

3

Influence of oxygen O2 on microwave saturation of EPR lines of plants carbonized at 650°c and potential application in medicine

Pilawa B., Bartłomiejczyk S., Krzesińska M., Pusz S., Zachariasz J., Wałach W.

Engineering of Biomaterials

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2008

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Vol. 11, no. 73

9-11

EN

Electron paramagnetic resonance spectroscopy (EPR) was used to examination of spin-lattice relaxation in vascular plants carbonized at 650°C. Application of EPR method of continuous microwave signal saturation in medicine was proposed. The first derivative EPR spectra of pyrolysed bamboo and yucca were measured for samples in air and in vacuum. Influence of microwave power in the range 0.7-100 mW on amplitudes of EPR lines were evaluated. It was stated that amplitudes of the studied carbon materials increase with increasing of microwave power in the studied range. Saturation of EPR lines was not observed, so fast spin-lattice relaxation processes exist in the analyzed materials. Changes of EPR amplitudes for samples in air were slower than for evacuated samples. This effect may be used for determination of oxygen contents in the biological cells cultures and for analysis of optimal parameters of photodynamic therapy of cancer.

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Comparatwe EPR analysis of oxygen interactions with plants carbonized at different temperatures

Bartłomiejczyk S., Pilawa B., Krzesińska M., Pusz S., Zachariasz J., Wałach W.

Engineering of Biomaterials

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2008

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Vol. 11, no. 73

3-5

EN

Carbon materials, bamboo (Bambusa vulagris) and yucca (Yucca flaccida) pyrolysed at 550°C, 750°C and 950°C, were tested as oximetric probes by electron paramagnetic resonance spectroscopy at X-band (9.3 GHz). The following parameters of the spectra: amplitude, linewidth and g-factor, were determined. Influence of oxygen molecules 02 on EPR spectra of the individual carbon materials was compared. Strong EPR spectra were recorded for samples carbonized at 550°C and weak signals were obtained for plants carbonized at higher temperatures: 750°C and 950°C. It was stated that amplitudes of EPR lines of all the carbonized plants decrease in the air environment compared to amplitudes of spectra measured in vacuum. This effect increases with degree of vacuum. Changes in the EPR spectra of samples studied in the air environment may be applied in medicine to determination of oxygen content in different cells. Because of strong resonance signals as oximetric probes we proposed bamboo and yucca carbonized at 550°C, and we rejected plants carbonized at 750°C and 950°C with Iow EPR signals.

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Nowe termowrażliwe reaktywne polietery oparte na glicydolu

Dworak A., Trzebicka B., Wałach W., Utrata A.

Polimery

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2003

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T. 48, nr 7-8

484-489

PL

Artykuł stanowi podsumowanie dotychczasowych prac Autorów nad wykorzystaniem glicydolu (2,3-epoksypropano-lu-1) do otrzymania reaktywnych amfifilowych polieterów charakteryzujących się w roztworach wodnych dolną krytyczną temperaturą rozpuszczalności (LCST). Omówiono syntezy liniowych i grzebieniowych homopolimerów glicydolu. Przedstawiono dwie metody syntezy takich polimerów o regulowanym stosunku fragmentów hydrofilowych do fragmentów hydrofobowych. Pierwsza z nich polega na estryfikacji homo-polimeru glicydolu bezwodnikiem octowym i prowadzi do bezładnych termowrażliwych kopolimerów glicydolu z octanem glicydolu. Druga opiera się na uzyskiwaniu w procesie anionowej żyjącej kopolimeryzacji kopolimerów triblokowych zawierających centralny hydrofilowy blok poli(tlenku etylenu) (PEOX) i dwa boczne hydrofobowe bloki poli(acetalu glicydolu) (PAG1). W dwóch szeregach kopolimerów blokowych różniących się masami molowymi poszczególnych bloków zbadano wpływ stosunku EOX/AG1 na wartość Tc (temperatury zmętnienia roztworu) tych termowrażliwych produktów.

EN

The article summarizes the present research works of authors on application of glycidol [(2,3-epoxypropanol-1), see equation (1)] to obtain the reactive amphiphilic polyethers showing the lower critical solution temperature (LCST) in aqueous solutions. The conditions of the syntheses of linear and comb- like glycidol homopolymers; [equations (2)-(5)] have been discussed. Two basic methods of the synthesis of the polymers with controlled ratio of hydrophilic and hydrophobic segments were presented. The first one is an esterification of glycidol homopolymer with acetic anhydride [equation (7)] and leads to random thermo-sensitive copolymers of glycidol with glycidol acetate (Table 2). The other method let obtain, in the process of anionic living copolymerization, triblock copolymers containing the central hydrophilic block of polyethylene oxide (PEOX) and two hydrophobic side blocks of polyglycidol acetal (PAGI) [equation (8), Table 3]. The effect of EOX/AGI ratio on LCST value (Fig. 1) of these thermo-sensitive products was investigated for two series of block copolymers differing with molar masses of particular blocks.

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New materials from 2,3-epoxypropanol-1

Dworak A., Trzebicka B., Wałach W.

Zeszyty Naukowe. Chemia / Politechnika Śląska

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1999

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z. 140

135-138

EN

The conditions for controlled synthesis of polymers of 2,3-epoxypropanol-1 are described. Based upon these conditions, hydrophilic and amphiphilic block copolymers of this monomer with ethylene oxide and with styrene were obtained and their were properties studied. A reactive macromonomer with a hydrophilic polyether chain and a polymerizable styrene end group was synthesized and its application as a surfmer was studied.

PL

Opisano warunki kontrolowanej syntezy polimerów 2,3-epoksypropanolu-1. W oparciu o te warunki otrzymano hydrofilowe i amfifilowe kopolimery blokowe tego monomeru oraz zbadano ich właściwości. Zsyntetyzowano reaktywny makromonomer o hydrofilowym łańcuchu polieterowym z polimeryzowalną styrenową grupą końcową oraz zbadano jego wykorzystanie jako surfmeru.