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Kolmas J.,Medical University of Warsaw | Sobczak M.,Medical University of Warsaw | Oledzka E.,Medical University of Warsaw | Nalecz-Jawecki G.,Medical University of Warsaw | Debek C.,Institute for Engineering of Polymer Materials and Dies
International Journal of Molecular Sciences | Year: 2014

In this study, new composite bisphosphonate delivery systems were obtained from polyurethanes (PUs) and nanocrystalline hydroxyapatite (HA). The biodegradable PUs were first synthesized from poly(ε-caprolactone) diols (PCL diols), poly(ethylene adipate) diol, 1,6-hexamethylene diisocyanate, 1,4-butanediol and HA. Moreover, the PCL diols were synthesized by the ring-opening polymerization catalysed by the lipase from Candida antarctica. Next, composite drug delivery systems for clodronate were prepared. The mechanical properties of the obtained biomaterials were determined. The cytotoxicity of the synthesized polymers was tested. The preliminary results show that the obtained composites are perspective biomaterials and they can be potentially applied in the technology of implantation drug delivery systems. © 2014 by the authors; licensee MDPI, Basel, Switzerland.


Sobczak M.,Medical University of Warsaw | Debek C.,Institute for Engineering of Polymer Materials and Dies | Gos P.,Medical University of Warsaw
E-Polymers | Year: 2010

A series of polyurethanes (PURs) were prepared by metal-free method, containing polycaprolactone (PCL) as the soft segment with molecular weights of 1600, 2400 and 2600. PCL was obtained by the ring-opening polymerization of e-caprolactone in the presence L-alanine and L-phenyloalanine. The structure of synthesized oligoesters and PURs were spectroscopically confirmed. The molecular weights, mechanical and thermal properties of the obtained materials were reported.


Sobczak M.,Medical University of Warsaw | Kamysz W.,Medical University of Gdansk | Kamysz W.,Research and Development Laboratory | Tyszkiewicz W.,Military Institute of Chemistry and Radiometry | And 8 more authors.
Reactive and Functional Polymers | Year: 2014

The effective synthesis of citropin-polymer conjugates was described in this paper. The obtained biodegradable polymeric matrices and polymeric conjugates were characterized using 1H or 13C NMR and Fourier transform infrared spectroscopies, gel permeation chromatography and scanning electron microscopy. Toxicity of polymers was evaluated with bacterial luminescence test and two protozoan assays. The in vitro release study of citropin from the obtained conjugates was investigated. The preliminary results of antimicrobial activity of the obtained macromolecular conjugates against Bacillus anthracis, Enterococcus hirae and Staphylococcus aureus were also discussed. The peptide had a high level of antimicrobial activity during 3-5 weeks of the degradation process. The development of biodegradable citropin systems should be of a great interest in the delivery systems of antimicrobial agents. © 2014 Published by Elsevier B.V.


Sasimowski E.,Lublin University of Technology | Sikora J.W.,Lublin University of Technology | Krolikowski B.,Institute for Engineering of Polymer Materials and Dies
Polimery/Polymers | Year: 2014

The paper presents a description of a modern direct screw drive carried out by a torque motor of a torque 300 Nm, maximum rotational speed 500 rpm and power 15.7 kW. The operation of the torque, its advantages and disadvantages were described. In the extruder plasticizing system in the feed opening zone and part of the feed zone, an exchangeable smooth sleeve and a grooved sleeve with 6 or 8 longitudinal grooves were used. For research, low density polyethylene of the commercial name MalenE and symbol FGNX 23-D006 was used. In the extruder barrel, a special screw was mounted 25 mm in diameter and L/D = 24, with elements of intensive shearing and mixing, constructionally adapted to the grooved section. The research was conducted in the wide range of rotational screw speeds from 1.67 to 8.33 rps.


Sobczak M.,Medical University of Warsaw | Debek C.,Institute for Engineering of Polymer Materials and Dies | Oledzka E.,Medical University of Warsaw | Nalecz-Jawecki G.,Medical University of Warsaw | And 2 more authors.
Journal of Polymer Science, Part A: Polymer Chemistry | Year: 2012

A series of biomedical polyurethane elastomers (PURs) based on poly(ester-carbonate)s (PECs) and polycarbonates (PCs) were synthesized and spectrally characterized fully. PEC or PC diols were synthesized by the ring-opening polymerization of ε-caprolactone, trimethylene carbonate, and neopentyl carbonate catalyzed by lipase from Candida antarctica. PURs were prepared by free-metal method from PEC or PC diols and 4,4'-methylenebis(phenyl isocyanate), with 1,4-butanediol as a chain extender. The physical and mechanical properties as well as hydrolytic stability of the obtained PURs were determined. The toxicity of the received polymers was evaluated using bacterial luminescence test and two protozoans assays. The presented preliminary studies suggest that PEC or PC diols prepared in this way might be applied for the synthesis of biomedical PURs with improved hydrolytic stability. © 2012 Wiley Periodicals, Inc.

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