Electrospinning of biodegradable polyester urethane: Effect of polymer-solution conductivity

This work deals with an investigation of fabrications of nanofibres based on biodegradable polylactic-acid/polyethylene-glycolchain- linked copolymers, using the electrospinning technique. Crucial attention is paid to describing the effect of polymer-solution conductivity on the morphology of the resulting nanofibres. Nanofibre systems were studied with scanning electron microscopy and the subsequent image analysis of nanofibre diameters. Hydrolytical degradability of the investigated copolymers was studied using gel permeation chromatography. The results show a significant effect of polymer-solution conductivity on the quality of nanofibres.Czech Science Foundation [15-08287Y]; Ministry of Education, Youth and Sports of the Czech Republic [LO1504]; Internal Grant Agency of TBU in Zlin [IGA/CPS/2015/003

Degradation behaviour of PLA-based polyesterurethanes under abiotic and biotic environments

Study was conducted on the degradation of polyurethanes based on Poly(lactic acid)/Poly(ethylene glycol), containing three differing concentrations of di-isocyanate compound, under three conditions (hydrolytic, thermal and composting). In the hydrolysis study, the effect of temperature and time were studied by techniques including weighting and GPC. Thermal decomposition was examined by thermogravimetry and mass spectroscopy. Composting was performed under standardized conditions and the amount of CO2 was measured. It was found that hydrolysis of the material started almost immediately after exposure to a water environment at both investigated temperatures (37°C and 55°C), whereas weight loss exhibited a certain delay. Thermal decomposition of the studied materials started below 230°C and lactide was identified as the main product. A biodegradation experiment showed that all the investigated samples successfully (>80%) mineralized within 90 days under composting conditions. © 2016 Elsevier Ltd. All rights reserved.LO1504, MEYS, Ministry of Education, Youth and SportsMinistry of Education, Youth and Sports of the Czech Republic, under the NPU I programme [LO1504

N-[2-(Cyclohexylamino)-2-oxoethyl]-N-(4-octyloxy) phenyl-prop-2-enamide

N-[2-(Cyclohexylamino)-2-oxoethyl]-N-(4-octyloxy)phenyl-prop-2-enamide was prepared in good yield by coupling of 4(octyloxy)aniline, Cyclohexyl isocyanide, paraformaldehyde and acrylic acid by multicomponent Ugi reaction, at room temperature. The structure of the newly synthesized tripeptoid derivative was well characterized using elemental analysis, FTIR, NMR and mass spectral data. © 2016 by the authors; licensee MDPI, Basel, Switzerland.DE-AC02-05CH11231, DOE, U.S. Department of EnergyMSMT CR-USA Kontakt II [LH14050]; Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy [DE-AC02-05CH11231]; Ministry of Education, Youth and Sports of the Czech Republic - NPU Program I [LO1504

Enhancement of temozolomide stability by loading in chitosan-carboxylated polylactide-based nanoparticles

In the presented work, amphiphilic nanoparticles based on chitosan and carboxy-enriched polylactic acid have been prepared to improve the stability of the pro-drug temozolomide in physiological media by encapsulation. The carrier, with a diameter in the range of 150–180 nm, was able to accommodate up to 800 μg of temozolomide per mg of polymer. The obtained formulation showed good stability in physiological condition and preparation media up to 1 month. Temozolomide loaded inside the carrier exhibited greater stability than the free drug, in particular in simulated physiological solution at pH 7.4 where the hydrolysis in the inactive metabolite was clearly delayed. CS-SPLA nanoparticles demonstrated a pH-dependent TMZ release kinetics with the opportunity to increase or decrease the rate. Mass spectroscopy, UV-Vis analysis, and in vitro cell tests confirmed the improvement in temozolomide stability and effectiveness when loaded into the polymeric carrier, in comparison with the free drug. © 2017, The Author(s).15-08287Y, GACR, Grantová Agentura České Republiky; 15-08287Y, GAČR, Grantová Agentura České Republiky; CZ.1.05/2.1.00/19.0409, MŠMT, Ministerstvo Školství, Mládeže a Tělovýchovy; LO1504, MŠMT, Ministerstvo Školství, Mládeže a TělovýchovyCzech Science Foundation [15-08287Y]; Ministry of Education, Youth and Sports of the Czech Republic [LO1504, CZ.1.05/2.1.00/19.0409]; Internal Grant Agency of the Tomas Bata University in Zlin [IGA/CPS/2016/004

Nanoparticles based on star-shaped carboxy-terminated polylactide and chitosan for controlled release applications

In this work chitosan based nanoparticles were prepared and modified by a star-shaped carboxy-terminated polylactide (S-PLA) in order to reduce the doxorubicin burst effect in physiological solution. S-PLA was prepared by polycondensation reaction using pentetic acid as a core molecule and methansulfonic acid as catalyst and linked to chitosan backbone through coupling reaction. Afterwards, chitosan-(S-PLA) modified nanoparticles loaded with doxorubicin were prepared by polyelectrolytes complexation method using dextran sulphate sodium salt as polyanion. Results show nanoparticles with diameter in the range 100-200 nm, spherical shape and ζ-potential between 27-35 mV. The presence of (S-PLA) side chain does not influence the encapsulation efficiency of the drug but strongly reduce the initial burst effect compared with unmodified chitosan.15-08287Y, GACR, Czech Science Foundatio

Influence of polylactide modification with blowing agents on selected mechanical properties

The article presents research of modification of PLA with four types of blowing agents with a different decomposition characteristic. Modifications were made in both cellular extrusion and injection molding processes. The obtained results show that dosing blowing agents have the influence on mechanical properties and structure morphology. Differences in the obtained results are also visible and significant between cellular processes

Effect of plasma treatment on the release kinetics of a chemotherapy drug from biodegradable polyester films and polyester urethane films

Investigation was made into the effect of plasma treatment on the release kinetics of the drug Temozolomide (TMZ) from thin, biodegradable polyester films, comprising polylactic acid (PLA) and polyester urethane. The authors utilized two systems to achieve this, the first being diffuse coplanar surface barrier discharge, applying air as the gaseous medium, while the other involved capacitively coupled radio frequency discharge plasma under an argon atmosphere with hexamethyldisiloxane. Results showed that both forms of plasma treatment positively reduced the undesirable burst effect and benefited the release rate of TMZ. The hydrolytic degradability of the materials was slightly enhanced following hydrophilization, whereas the same diminished after hydrophobization had taken place. This was especially true for PLA due to modification of its wettability. © 2017 Taylor & Francis.02/0199/14, VEGA, Vedecká Grantová Agentúra MŠVVaŠ SR a SAV; APVV-14-0518, APVV, Agentúra na Podporu Výskumu a Vývoja; QJ1310254, MZe, Ministerstvo Zemědělství; SAV, Slovenská Akadémia Vied; 15-08287Y, GACR, Grantová Agentura České Republiky; CZ.1.05/2.1.00/19.0409; LO1504Czech Science Foundation [15-08287Y]; Ministry of Agriculture of the Czech Republic [QJ1310254]; Ministry of Education, Youth and Sports of the Czech Republic [LO1504, CZ.1.05/2.1.00/19.0409]; Ministry of Education, Science, Research and Sports of the Slovak Republic; Slovak Academy of Sciences, as a part of the "VEGA" project [02/0199/14]; Slovak Research and Development Agency [APVV-14-0518

Differential branching fraction and angular analysis of the decay B0→K∗0μ+μ−

The angular distribution and differential branching fraction of the decay B 0→ K ∗0 μ + μ − are studied using a data sample, collected by the LHCb experiment in pp collisions at s√=7 TeV, corresponding to an integrated luminosity of 1.0 fb−1. Several angular observables are measured in bins of the dimuon invariant mass squared, q 2. A first measurement of the zero-crossing point of the forward-backward asymmetry of the dimuon system is also presented. The zero-crossing point is measured to be q20=4.9±0.9GeV2/c4 , where the uncertainty is the sum of statistical and systematic uncertainties. The results are consistent with the Standard Model predictions

Opposite-side flavour tagging of B mesons at the LHCb experiment

The calibration and performance of the oppositeside flavour tagging algorithms used for the measurements of time-dependent asymmetries at the LHCb experiment are described. The algorithms have been developed using simulated events and optimized and calibrated with B + →J/ψK +, B0 →J/ψK ∗0 and B0 →D ∗− μ + νμ decay modes with 0.37 fb−1 of data collected in pp collisions at √ s = 7 TeV during the 2011 physics run. The oppositeside tagging power is determined in the B + → J/ψK + channel to be (2.10 ± 0.08 ± 0.24) %, where the first uncertainty is statistical and the second is systematic

Search for CP violation in D+→ϕπ+ and D+s→K0Sπ+ decays

A search for CP violation in D + → ϕπ + decays is performed using data collected in 2011 by the LHCb experiment corresponding to an integrated luminosity of 1.0 fb−1 at a centre of mass energy of 7 TeV. The CP -violating asymmetry is measured to be (−0.04 ± 0.14 ± 0.14)% for candidates with K − K + mass within 20 MeV/c 2 of the ϕ meson mass. A search for a CP -violating asymmetry that varies across the ϕ mass region of the D + → K − K + π + Dalitz plot is also performed, and no evidence for CP violation is found. In addition, the CP asymmetry in the D+s→K0Sπ+ decay is measured to be (0.61 ± 0.83 ± 0.14)%