Polyester-based nanostructures are widely studied as drug-delivery systems due to their biocompatibility and biodegradability. They are already used in the clinic. In this work, we describe a new and simple biodegradable and biocompatible system as the Food and Drug Administration approved polyesters (poly-ε-caprolactone, polylactic acid, and poly(lactic- co-glycolic acid)) for the delivery of the anticancer drug paclitaxel (PTX) as a model drug. A hydrophobic polyester, poly(propylene succinate) (PPS), was prepared from a nontoxic alcohol (propylene glycol) and monomer from the Krebs's cycle (succinic acid) in two steps via esterification and melt polycondensation. Furthermore, their amphiphilic block copolyester, poly(ethylene oxide monomethyl ether)- block-poly(propylene succinate) (mPEO- b-PPS), was prepared by three steps via esterification followed by melt polycondensation and the addition of mPEO to the PPS macromolecules. Analysis of the in vitro cellular behavior of the prepared nanoparticle carriers (NPs) (enzymatic degradation, uptake, localization, and fluorescence resonance energy-transfer pair degradation studies) was performed by fluorescence studies. PTX was loaded to the NPs of variable sizes (30, 70, and 150 nm), and their in vitro release was evaluated in different cell models and compared with commercial PTX formulations. The mPEO- b-PPS copolymer analysis displays glass transition temperature < body temperature < melting temperature, lower toxicity (including the toxicity of their degradation products), drug solubilization efficacy, stability against spontaneous hydrolysis during transport in bloodstream, and simultaneous enzymatic degradability after uptake into the cells. The detailed cytotoxicity in vitro and in vivo tumor efficacy studies have shown the superior efficacy of the NPs compared with PTX and PTX commercial formulations.

• MeSH
• micely MeSH
• myši inbrední BALB C MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• nanočástice škodlivé účinky   chemie   metabolismus   MeSH
• paclitaxel aplikace a dávkování   farmakokinetika   MeSH
• polyestery chemická syntéza   chemie   MeSH
• polyethylenglykoly chemie   MeSH
• polypropyleny chemie   MeSH
• protinádorové látky aplikace a dávkování   farmakokinetika   MeSH
• sukcináty chemie   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• micely MeSH
• paclitaxel MeSH
• polyestery MeSH
• polyethylenglykoly MeSH
• polypropyleny MeSH
• protinádorové látky MeSH
• sukcináty MeSH

To minimize non-specific protein adsorption on macroporous poly(glycidyl methacrylate) and poly(2-hydroxyethyl methacrylate) microspheres containing amino and/or carboxyl groups, the microspheres are coated with α,ω-bis-carboxy poly(ethylene glycol) and amino-terminated poly(ethylene glycol-co-propylene glycol) or α-methoxy-ω-amino poly(ethylene glycol). Adsorption of bovine serum albumin (BSA), γ-globulin, (125) I-BSA, pepsin, and chymotrypsin on neat and PEGylated microspheres is determined by UV-VIS spectroscopy of supernatants and eluates or by measurement of radioactivity in an ionization chamber. Neat and PEGylated microspheres adsorb 0.8-70% and 0.02-44% of protein, respectively.

• MeSH
• adsorpce MeSH
• biotechnologie metody   MeSH
• chymotrypsin chemie   MeSH
• gama-globuliny chemie   MeSH
• kyseliny polymethakrylové chemie   MeSH
• mikrosféry * MeSH
• molekulární struktura MeSH
• polyethylenglykoly chemie   MeSH
• polyhydroxyethylmethakrylát chemie   MeSH
• radioizotopy jodu chemie   MeSH
• sérový albumin hovězí chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• chymotrypsin MeSH
• gama-globuliny MeSH
• kyseliny polymethakrylové MeSH
• polyethylenglykoly MeSH
• polyglycidyl methacrylate MeSH Prohlížeč
• polyhydroxyethylmethakrylát MeSH
• radioizotopy jodu MeSH
• sérový albumin hovězí MeSH

Raman, attenuated total reflectance FTIR, near-infrared spectroscopy, and DFT calculations have been used in a study of aqueous solutions of three tri-block copolymers poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) or PEO-PPO-PEO with commercial names Pluronic PE6200, PE6400 and F68. It is shown that the process of micellization as a response to increased temperature is reflected in the hydroxyl stretching region of infrared and Raman spectra, which contains information both about restructuring of water and changes of polymer chains in polymer/water aggregates. Raman spectra exhibit differences between individual Pluronics even at temperatures below the critical micellization temperature (CMT). According to the attenuated total reflection (ATR) FTIR spectra, the same five water coordination types defined by the number of donated/accepted hydrogen bonds are present in interacting water as in bulk water. It indicates that models considering mixed states of water with different hydrogen bonding environments provide appropriate descriptions of bound water both below and above the CMT. Above the CMT, aggregate hydration increases in the order PE6400 < PE6200 < F68, although that does not fully correspond to the EO/PO ratio, and points to the differences in microstructure of aggregates formed by each copolymer. This study relates nanoscale phenomena (hydrophobic and hydrophilic hydration) with the mesoscale phenomenon of micellization.

• MeSH
• blízká infračervená spektroskopie MeSH
• kvantová teorie MeSH
• micely MeSH
• polyethylenglykoly chemie   MeSH
• povrchové vlastnosti MeSH
• propylenglykoly chemie   MeSH
• Ramanova spektroskopie MeSH
• simulace molekulární dynamiky MeSH
• spektroskopie infračervená s Fourierovou transformací MeSH
• velikost částic MeSH
• voda chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• micely MeSH
• PEO-PPO-PEO MeSH Prohlížeč
• poly(ethyleneoxide)(13)-poly(propyleneoxide)(30)-poly(ethyleneoxide)(13) block copolymer MeSH Prohlížeč
• polyethylenglykoly MeSH
• propylenglykoly MeSH
• voda MeSH

Poly(2-alkenyl-2-oxazoline)s are promising functional polymers for a variety of biomedical applications, such as drug delivery systems, peptide conjugates, or gene delivery. In this study, poly(2-isopropenyl-2-oxazoline) (PIPOx) is prepared through free-radical polymerization initiated with azobisisobutyronitrile. Reactive 2-oxazoline units in the side chain support an addition reaction with different compounds containing a carboxylic group, which facilitates the preparation of polymers labeled with two different fluorescent dyes. The cytotoxicities of 2-oxazoline monomers, PIPOx, and fluorescently labeled PIPOx are evaluated in vitro using an 3-(4,5-Dimethyldiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and ex vivo using a cell proliferation assay with adenosine triphosphate bioluminescence. The cell uptake of labeled PIPOx is used to determine the colocalization of PIPOx with cell organelles that are part of the endocytic pathway. For the first time, it is shown that poly(2-isopropenyl-2-oxazoline) is a biocompatible material and is suitable for biomedical applications; further, its immunomodulative properties are evaluated.

• Klíčová slova
• biocompatibility, cell proliferation, fluorescence, functionalization of polymers, poly(2-isopropenyl-2-oxazoline), splenocytes,
• MeSH
• biokompatibilní materiály chemická syntéza   chemie   farmakologie   MeSH
• buněčná smrt účinky léků   MeSH
• buňky 3T3 MeSH
• endocytóza účinky léků   MeSH
• fibroblasty cytologie   MeSH
• fluorescenční spektrometrie MeSH
• imunomodulace účinky léků   MeSH
• konfokální mikroskopie MeSH
• myši inbrední BALB C MeSH
• myši MeSH
• organely účinky léků   metabolismus   MeSH
• oxazoly chemická syntéza   chemie   farmakologie   MeSH
• polymery chemická syntéza   chemie   farmakologie   MeSH
• polypropyleny chemická syntéza   chemie   farmakologie   MeSH
• proliferace buněk účinky léků   MeSH
• slezina cytologie   MeSH
• viabilita buněk účinky léků   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• biokompatibilní materiály MeSH
• oxazoly MeSH
• poly(2-isopropenyl-2-oxazoline) MeSH Prohlížeč
• polymery MeSH
• polypropyleny MeSH

A new targeted intravenous conjugate of nystatin with pentaerythritol poly(ethylene glycol)ether has been prepared and characterised (NY(4)-sPEG, M=25 160). The conjugate contains a beta-d-glucopyranoside molecular switch sensitive to beta-glucosidases (E.C.3.2.1.21), which are specifically present in the enzyme outfit of fungal pathogens. The investigated conjugate is stable under in vitro conditions for 24h (solution of phosphate buffer pH=7.4). Spectrophotometrically controlled releasing of nystatin in model medium containing beta-glucosidase ((Aspergillus niger) 2mg/mL, 66.6 units/g; pH 7.4, 2 x 10(-2)M), reported decomposition half-life of conjugate tau(1/2)=(88+/-2)s. This implies that releasing of nystatin is controlled only enzymatically.

• MeSH
• antifungální látky aplikace a dávkování   chemie   metabolismus   MeSH
• Aspergillus niger enzymologie   MeSH
• celulasy izolace a purifikace   metabolismus   MeSH
• farmaceutická chemie MeSH
• farmaceutická technologie metody   MeSH
• gelová chromatografie MeSH
• hydrolýza MeSH
• kinetika MeSH
• koncentrace vodíkových iontů MeSH
• léky s prodlouženým účinkem MeSH
• magnetická rezonanční spektroskopie MeSH
• nosiče léků * MeSH
• nystatin aplikace a dávkování   chemie   metabolismus   MeSH
• poločas MeSH
• polyethylenglykoly chemie   MeSH
• příprava léků MeSH
• propylenglykoly chemie   MeSH
• pufry MeSH
• rozpustnost MeSH
• spektrofotometrie ultrafialová MeSH
• stabilita léku MeSH
• vysokoúčinná kapalinová chromatografie MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antifungální látky MeSH
• celulasy MeSH
• léky s prodlouženým účinkem MeSH
• nosiče léků * MeSH
• nystatin MeSH
• pentaerythritol MeSH Prohlížeč
• polyethylenglykoly MeSH
• propylenglykoly MeSH
• pufry MeSH

In this study, a sensitive platform was designed for the electrocatalytical oxidation and recognition of ascorbic acid (AA) based on poly(β-cyclodextrin) modified glassy carbon electrode (p(β-CD-GCE). Electropolymerization of β-CD on the surface of GCE was performed on the potential range of -1 to 1.5 V. So, a novel biopolymer was prepared on the surface of GCE towards sensitive recognition of AA in human plasma samples. The developed platform has good sensitivity and accuracy for electrooxidation and detection of AA with lower limit of quantification (LLOQ) of 1 nM and linear range of 1 nM to 100 mM. Moreover, the designed electrochemical sensor was employed for the analysis of AA on human plasma samples with high sensitivity. Based on advantages of p(β-CD) prepared by electropolymerization procedure (green, fast, homogeny, and efficient eletrocatalytical behaviour), this conductive biopolymer showed excellent analytical behaviour towards electrooxidation of AA. It is expected that the prepared polymeric interface is able to use in the analysis of biological species in clinical samples.

• Klíčová slova
• advanced biopolymer, biocompatible materials, electrochemical oxidation, electropolymerization, sensor technology, β-cyclodextrin,
• MeSH
• beta-cyklodextriny MeSH
• biokompatibilní materiály MeSH
• biopolymery MeSH
• elektrochemické techniky * metody   MeSH
• kyselina askorbová * MeSH
• lidé MeSH
• propylenglykoly MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• beta-cyklodextriny MeSH
• biokompatibilní materiály MeSH
• biopolymery MeSH
• kyselina askorbová * MeSH
• poly(beta-cyclodextrin) MeSH Prohlížeč
• propylenglykoly MeSH

The interactions of three alcohols, namely, 2-butanol (BuOH), 3-methyl-2-butanol (MeBuOH), and 3,3-dimethyl-2-butanol (Me2BuOH) with propylene oxide octamer (PO8) and the copolymers (EO)8(PO)13(EO)8(L35) and (EO)13(PO)30(EO)13(L64) in D2O were studied using (13)C NMR spectra and relaxations and (1)H PFG NMR diffusion measurements. For L64, it was shown that the temperature at which the PO chain starts to change its conformation under dehydration decreases by 6 K for each additional methyl group in the alcohol molecule (i.e. with increasing its hydrophobicity), and the analogous conformation states are attained at temperatures approximately 10 K lower compared using ketonic analogs of the alcohols under the same conditions. Also, the first signs of L64 aggregation, according to the normalized diffusion coefficients, are at temperatures 7, 10, and 13 K lower for BuOH, MeBuOH, and Me2BuOH, respectively. These effects are much weaker for (PO)13 in L35 or nonexistent for (PO)8 in PO8, thus showing the role of cooperativity in dehydration and aggregation processes. According to diffusion measurements, the molar fraction of the alcohol hydrogen bonded to L64 increases with its hydrophobicity and, in an apparent conflict with thermodynamics, with increasing temperature at which also higher NOE can be observed. Strong hydrogen bond interaction, which is in cooperation with hydrophobic interaction, does not preclude the exchange between bound and free states of the alcohol, however. Using (13)C transverse relaxation, its correlation time is shown to be of the order of 10 ms.

• MeSH
• alkoholy chemie   MeSH
• difuze MeSH
• hydrofobní a hydrofilní interakce MeSH
• magnetická rezonanční spektroskopie MeSH
• micely MeSH
• polyethylenglykoly chemie   MeSH
• propylenglykoly chemie   MeSH
• termodynamika MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• alkoholy MeSH
• micely MeSH
• PEO-PPO-PEO MeSH Prohlížeč
• polyethylenglykoly MeSH
• propylenglykoly MeSH

Chromatographic behavior of block (co)oligomers of oxyethylene (EO) and oxypropylene (PO) surfactants in reversed-phase HPLC (RP-HPLC) was investigated. The retention of EO/PO block (co)oligomers depends on the distribution of the individual monomer repeat units, but the sequence of the individual blocks also plays a (less significant) role. The enthalpic and entropic contributions of the EO and PO repeat units to the retention were determined from the data measured at changing temperature. In RP-HPLC, the effect of the repeat PO units on separation is higher than the influence of the repeat EO units. In addition to the enthalpic contributions, the retention is significantly influenced by the entropy (possibly by the change of conformation and solvation of adsorbed molecules); dual molar mass distribution according to the number of EO and PO units complicates correct assignment of the chromatographic peaks to the individual (co)oligomers in complex samples based only on the chromatographic retention data. In spite of imperfect chromatographic separation, HPLC coupled with positive ion mode atmospheric pressure chemical ionization mass spectrometry allow identifying unambiguously the dual monomer distribution in the samples of EO-PO block (co)oligomers.

• MeSH
• epoxidové sloučeniny chemie   MeSH
• ethylenoxid chemie   MeSH
• hmotnostní spektrometrie metody   MeSH
• polyethylenglykoly chemie   MeSH
• termodynamika MeSH
• vysokoúčinná kapalinová chromatografie metody   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• epoxidové sloučeniny MeSH
• ethylenoxid MeSH
• polyethylenglykoly MeSH
• propylene oxide MeSH Prohlížeč

New amphiphilic diblock polymer nanotherapeutics serving simultaneously as a drug delivery system and an inhibitor of multidrug resistance were designed, synthesized, and evaluated for their physico-chemical and biological characteristics. The amphiphilic character of the diblock polymer, containing a hydrophilic block based on the N-(2-hydroxypropyl)methacrylamide copolymer and a hydrophobic poly(propylene oxide) block (PPO), caused self-assembly into polymer micelles with an increased hydrodynamic radius (Rh of approximately 15nm) in aqueous solutions. Doxorubicin (Dox), as a cytostatic drug, was bound to the diblock polymer through a pH-sensitive hydrazone bond, enabling prolonged circulation in blood, the delivery of Dox into a solid tumor and the subsequent stimuli-sensitive controlled release within the tumor mass and tumor cells at a decreased pH. The applicability of micellar nanotherapeutics as drug carriers was confirmed by an in vivo evaluation using EL4 lymphoma-bearing C57BL/6 mice. We observed significantly higher accumulation of micellar conjugates in a solid tumor because of the EPR effect compared with similar polymer-drug conjugates that do not form micellar structures or with the parent free drug. In addition, highly increased anti-tumor efficacy of the micellar polymer nanotherapeutics, even at a sub-optimal dose, was observed. The presence of PPO in the structure of the diblock polymer ensured, during in vitro tests on human and mouse drug-sensitive and resistant cancer cell lines, the inhibition of P-glycoprotein, one of the most frequently expressed ATP-dependent efflux pump that causes multidrug resistance. In addition, we observed highly increased rate of the uptake of the diblock polymer nanotherapeutics within the cells. We suppose that combination of unique properties based on MDR inhibition, stimuli sensitiveness (pH sensitive activation of drug), improved pharmacokinetics and increased uptake into the cells made the described polymer micelle a good candidate for investigation as potential drug delivery system.

• Klíčová slova
• EPR effect, HPMA copolymer, Micellar drug conjugate, Multidrug resistance, P-glycoprotein inhibitor, Poly(propylene oxide),
• MeSH
• akrylamidy aplikace a dávkování   chemie   farmakokinetika   terapeutické užití   MeSH
• chemorezistence účinky léků   MeSH
• doxorubicin aplikace a dávkování   chemie   farmakokinetika   terapeutické užití   MeSH
• hydrofobní a hydrofilní interakce MeSH
• lidé MeSH
• micely * MeSH
• mnohočetná léková rezistence účinky léků   MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• nádory farmakoterapie   metabolismus   patologie   MeSH
• nosiče léků aplikace a dávkování   chemie   farmakokinetika   terapeutické užití   MeSH
• polymery aplikace a dávkování   chemie   farmakokinetika   terapeutické užití   MeSH
• propylenglykoly aplikace a dávkování   chemie   farmakokinetika   terapeutické užití   MeSH
• protinádorová antibiotika aplikace a dávkování   chemie   farmakokinetika   terapeutické užití   MeSH
• tumor burden účinky léků   MeSH
• uvolňování léčiv MeSH
• viabilita buněk účinky léků   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• akrylamidy MeSH
• doxorubicin MeSH
• micely * MeSH
• N-(2-hydroxypropyl)methacrylamide MeSH Prohlížeč
• nosiče léků MeSH
• polymery MeSH
• polypropylene glycol MeSH Prohlížeč
• propylenglykoly MeSH
• protinádorová antibiotika MeSH

The effect of recycling on the thermo-mechanical and water absorption behavior of polypropylene (PP)/sisal fiber and polylactic acid (PLA)/sisal fiber composites were studied. The PP-based non-biodegradable composites and PLA-based biodegradable composites were recycled for four times. The effect of recycling was determined by examining the morphology, thermo-mechanical properties, and water absorption behavior and the obtained results were compared. The results showed that the incorporation of sisal fibers in the PP and PLA matrix enhances the tensile modulus and percentage crystallinity of the composites. The tensile strength and modulus of the sisal fiber reinforced PP composites were not affected with recycling. Even though the tensile properties of PLA and PLA/sisal fiber reinforced composites are superior to PP and PP/sisal fiber composites, the PLA-based composites show a dramatic decrease in tensile strength and modulus after the first recycling due to the degradation of the polymer. The thermal stability of the PP/sisal fiber composites was not affected by the repeated recycling process. On the other hand, the PLA-based composites with higher sisal fiber content show a bit lower thermal stability after recycling. The PP-based composites show fluctuations in percentage crystallinity with recycling. On the other hand, a remarkable increase in percentage crystallinity for PLA and PLA-based composites was observed with increasing recycling times. Water diffusion study divulges that the diffusion of water into the polymer composites was reduced with recycling, irrespective of the polymer matrix.

• Klíčová slova
• Polylactic acid, Polypropylene, Thermomechanical properties,
• MeSH
• polyestery MeSH
• polypropyleny * MeSH
• recyklace MeSH
• voda * MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• poly(lactide) MeSH Prohlížeč
• polyestery MeSH
• polypropyleny * MeSH
• voda * MeSH