The modification of biomaterial surfaces has become increasingly relevant in the context of ongoing advancements in tissue engineering applications and the development of tissue-mimicking polymer materials. In this study, we investigated the layer-by-layer (LbL) deposition of polyelectrolyte multilayer protein reservoirs consisting of poly-l-lysine (PLL) and hyaluronic acid (HA) on the hydrophobic surface of poly(glycerol sebacate) (PGS) elastomer. Using the methods of isothermal titration calorimetry and surface plasmon resonance, we systematically investigated the interactions between the polyelectrolytes and evaluated the deposition process in real time, providing insight into the phenomena associated with film assembly. PLL/HA LbL films deposited on PGS showed an exceptional ability to incorporate bone morphogenetic protein-2 (BMP-2) compared to other growth factors tested, thus highlighting the potential of PLL/HA LbL films for osteoregenerative applications. The concentration of HA solution used for film assembly did not affect the thickness and topography of the (PLL/HA)10 films, but had a notable impact on the hydrophilicity of the PGS surface and the BMP-2 release kinetics. The release kinetics were successfully described using the Weibull model and hyperbolic tangent function, underscoring the potential of these less frequently used models to compare the protein release from LbL protein reservoirs.

• Klíčová slova
• BMP-2 release, Bioactive protein reservoirs, Layer-by-layer coating, Poly(glycerol sebacate), Surface modification,
• MeSH
• kyselina hyaluronová * chemie   MeSH
• nanočástice layer-by-layer MeSH
• polyelektrolyty MeSH
• polylysin * chemie   MeSH
• polymery MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• kyselina hyaluronová * MeSH
• poly(glycerol-sebacate) MeSH Prohlížeč
• polyelektrolyty MeSH
• polylysin * MeSH
• polymery MeSH

The present paper deals with the preparation and characterization of a conjugate of isoniazid (INH) with the block copolymer methoxypoly(ethylene glycol)-b-poly(L-lysine) (mPEG-b-PLL). The structure of the conjugate (mPEG-b-PLL-INH) was verified by means of (1)H NMR, GPC, infrared spectroscopy, elemental analysis and powder X-ray diffraction. The conjugate contains six l-lysine units with five INH molecules, which are attached by means of pH-sensitive amidine bond. Under in vitro conditions, the conjugate is hydrolyzed and isoniazid is released (pH 4; 37 °C; t(1/2) ≈ 10 h).

• MeSH
• isoniazid chemie   MeSH
• koncentrace vodíkových iontů MeSH
• molekulární struktura MeSH
• polyethylenglykoly chemie   MeSH
• polylysin analogy a deriváty   chemie   MeSH
• prášková difrakce MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• isoniazid MeSH
• mPEG-block-PLL MeSH Prohlížeč
• polyethylenglykoly MeSH
• polylysin MeSH

This study illustrates the synthesis of functionalized carbon quantum dots (CQDs) by the one-pot pyrolysis method. The functionalization agent used in CQD synthesis was poly l- lysine (PLL). Various physicochemical techniques were employed to confirm the successful formation of PLLCQD including High resolution transmission electron microscopy (HR-TEM), UV-Vis spectroscopy, fluorescence spectroscopy; Atomic force microscopy (AFM), X-ray Photoelectron Spectroscopy (XPS) and X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. The size of PLLCQD was confirmed by HRTEM and AFM. The synthesized PLLCQD shows bright blue fluorescence and has a quantum yield of 19.35%. The highest emission band was observed at 471nm when excited to 370nm. The prepared PLLCQD exhibited excellent antibacterial activity against Escherichia coli and Staphylococcus aureus with inhibition zone 7-20 mm. The concentrations of 0.9 to 0.1gmL-1 were studied to determine minimum inhibitory concentration (MIC) by the agar well diffusion assay method. MIC of 0.2gml -1 concentration of PLLCQD is achieved. The anti-angiogenic activity of PLLCQD was determined using (Chick Chorioallantoic Membrane) CAM assay. CAM assay is a reliable in -vivo model to study angiogenesis also; many stimulators and inhibitors have been examined by this method. This study proves higher antibacterial efficiency of PLLCQD over non functionalized CQD. PLLCQD was successfully employed in bio-imaging of the bacterial cell through fluorescence microscopy. Further, PLLCQD displayed cytotoxic effect on endothelial cells and inhibited blood vessel formation in the CAM model.

• Klíčová slova
• Antiangiogenesis, Antibacterial activity, Bioimaging, Carbon quantum dots, Poly l lysine,
• MeSH
• antibakteriální látky farmakologie   MeSH
• endoteliální buňky MeSH
• Escherichia coli MeSH
• kvantové tečky * chemie   MeSH
• lysin MeSH
• polylysin MeSH
• spektroskopie infračervená s Fourierovou transformací MeSH
• uhlík chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antibakteriální látky MeSH
• lysin MeSH
• polylysin MeSH
• uhlík MeSH

BACKGROUND: Cell tracking is a powerful tool to understand cellular migration, dynamics, homing and function of stem cell transplants. Nanoparticles represent possible stem cell tracers, but they differ in cellular uptake and side effects. Their properties can be modified by coating with different biocompatible polymers. To test if a coating polymer, poly(L-lysine), can improve the biocompatibility of nanoparticles applied to neural stem cells, poly(L-lysine)-coated maghemite nanoparticles were prepared and characterized. We evaluated their cellular uptake, the mechanism of internalization, cytotoxicity, viability and proliferation of neural stem cells, and compared them to the commercially available dextran-coated nanomag(®)-D-spio nanoparticles. RESULTS: Light microscopy of Prussian blue staining revealed a concentration-dependent intracellular uptake of iron oxide in neural stem cells. The methyl thiazolyl tetrazolium assay and the calcein acetoxymethyl ester/propidium iodide assay demonstrated that poly(L-lysine)-coated maghemite nanoparticles scored better than nanomag(®)-D-spio in cell labeling efficiency, viability and proliferation of neural stem cells. Cytochalasine D blocked the cellular uptake of nanoparticles indicating an actin-dependent process, such as macropinocytosis, to be the internalization mechanism for both nanoparticle types. Finally, immunocytochemistry analysis of neural stem cells after treatment with poly(L-lysine)-coated maghemite and nanomag(®)-D-spio nanoparticles showed that they preserve their identity as neural stem cells and their potential to differentiate into all three major neural cell types (neurons, astrocytes and oligodendrocytes). CONCLUSION: Improved biocompatibility and efficient cell labeling makes poly(L-lysine)-coated maghemite nanoparticles appropriate candidates for future neural stem cell in vivo tracking studies.

• Klíčová slova
• dextran, maghemite, nanoparticles, neural stem cells, poly(L-lysine),
• Publikační typ
• časopisecké články MeSH

N-(2-Hydroxypropyl)methacrylamide (HPMA) copolymers (pHPMA) containing 4-nitrophenyl ester (ONp) or thiazolidine-2-thione (TT) reactive groups in side chains and telechelic/semitelechelic pHPMA with TT groups were designed as highly hydrophilic biocompatible polymers suitable for chemical coating of polyelectrolyte-based DNA-containing nanoparticles bearing amino groups on the surface. The course of the coating reaction carried out in aqueous solution was evaluated on model self-assembling polyelectrolyte DNA/poly(L-lysine) (DNA/PLL) complexes either by monitoring the amount of residual polymer reactive groups by UV spectroscopy or by monitoring changes in the weight-average molecular weight and hydrodynamic size of the complexes using light scattering methods. Physicochemical stability of the coated complexes in buffered saline solution was also investigated. Contrary to uncoated particles, the coated complexes showed remarkable stability to aggregate in 0.15 M NaCl. Coating with pHPMA had practically no effect on the size distribution of the most stable complexes prepared by complexation of DNA with high-molecular-weight PLL (M(w) = 134 000) as shown by dynamic light scattering. The coating reaction was faster and more efficient with multivalent HPMA copolymers containing TT reactive groups than that with HPMA copolymers containing ONp groups.

• MeSH
• aminace MeSH
• chlorid sodný MeSH
• DNA chemie   MeSH
• hydrolýza MeSH
• kinetika MeSH
• kyseliny polymethakrylové chemie   MeSH
• molekulární struktura MeSH
• molekulová hmotnost MeSH
• nitrobenzeny chemie   MeSH
• polylysin chemie   MeSH
• spektrofotometrie ultrafialová MeSH
• thiazolidiny MeSH
• thiazoly chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 2-mercaptothiazoline MeSH Prohlížeč
• chlorid sodný MeSH
• DNA MeSH
• Duxon MeSH Prohlížeč
• kyseliny polymethakrylové MeSH
• nitrobenzeny MeSH
• polylysin MeSH
• thiazolidiny MeSH
• thiazoly MeSH

This paper reports on the synthesis, characterisation, and efficiency of a new intravenous conjugate of amphotericin B (AMB). Twelve molecules of AMB were attached to block copolymer poly(ethylene glycol)-b-poly(L-lysine) via pH-sensitive imine linkages. In vitro drug release studies demonstrated the conjugate (M(w)=26,700) to be relatively stable in human plasma and in phosphate buffer (pH 7.4, 37 degrees C). Controlled release of AMB was observed in acidic phosphate buffer (pH 5.5, 37 degrees C) with the half-life of 2 min. The LD(50) value determined in vivo (mouse) is 45 mg/kg.

• MeSH
• amfotericin B analogy a deriváty   chemická syntéza   MeSH
• antifungální látky chemická syntéza   farmakologie   MeSH
• chemické modely MeSH
• farmaceutická chemie metody   MeSH
• koncentrace vodíkových iontů MeSH
• molekulární konformace MeSH
• polyethylenglykoly chemie   MeSH
• polylysin chemie   MeSH
• polymery chemie   MeSH
• racionální návrh léčiv MeSH
• spektrofotometrie ultrafialová metody   MeSH
• teplota MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• amfotericin B MeSH
• antifungální látky MeSH
• polyethylenglykoly MeSH
• polylysin MeSH
• polymery MeSH

BACKGROUND: Poly-l-lysine (PLL) enhances nanoparticle (NP) uptake, but the molecular mechanism remains unresolved. We asked whether PLL may interact with negatively charged glycoconjugates on the cell surface and facilitate uptake of magnetic NPs (MNPs) by tumor cells. METHODS: PLL-coated MNPs (PLL-MNPs) with positive and negative ζ-potential were prepared and characterized. Confocal and transmission electron microscopy was used to analyze cellular internalization of MNPs. A colorimetric iron assay was used to quantitate cell-associated MNPs (MNPcell). RESULTS: Coadministration of PLL and dextran-coated MNPs in culture enhanced cellular internalization of MNPs, with increased vesicle size and numbers/cell. MNPcell was increased by eight- to 12-fold in response to PLL in a concentration-dependent manner in human glioma and HeLa cells. However, the application of a magnetic field attenuated PLL-induced increase in MNPcell. PLL-coating increased MNPcell regardless of ζ-potential of PLL-MNPs, whereas magnetic force did not enhance MNPcell. In contrast, epigallocatechin gallate and magnetic force synergistically enhanced PLL-MNP uptake. In addition, heparin, but not sialic acid, greatly reduced the enhancement effects of PLL; however, removal of heparan sulfate from heparan sulfate proteoglycans of the cell surface by heparinase III significantly reduced MNPcell. CONCLUSION: Our results suggest that PLL-heparan sulfate proteoglycan interaction may be the first step mediating PLL-MNP internalization by tumor cells. Given these results, PLL may facilitate NP interaction with tumor cells via a molecular mechanism shared by infection machinery of certain viruses.

• Klíčová slova
• glycoconjugate, heparan sulfate proteoglycan, magnetic nanoparticles, poly-l-lysine, tea catechin,
• MeSH
• buněčná membrána metabolismus   MeSH
• dextrany chemie   metabolismus   MeSH
• endoteliální buňky pupečníkové žíly (lidské) MeSH
• gliom farmakoterapie   patologie   MeSH
• HeLa buňky MeSH
• heparansulfát proteoglykany chemie   metabolismus   MeSH
• lidé MeSH
• magnetické nanočástice aplikace a dávkování   chemie   MeSH
• magnetické pole MeSH
• nádorové buněčné linie MeSH
• polylysin chemie   metabolismus   farmakokinetika   MeSH
• polysacharid-lyasy metabolismus   MeSH
• transmisní elektronová mikroskopie MeSH
• železo metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• dextrany MeSH
• heparansulfát proteoglykany MeSH
• heparitinsulfate lyase MeSH Prohlížeč
• magnetické nanočástice MeSH
• polylysin MeSH
• polysacharid-lyasy MeSH
• železo MeSH

New surface-modified iron oxide nanoparticles were developed by precipitation of Fe(II) and Fe(III) salts with ammonium hydroxide and oxidation of the resulting magnetite with sodium hypochlorite, followed by the addition of poly( L-lysine) (PLL) solution. PLL of several molecular weights ranging from 146 ( L-lysine) to 579 000 was tested as a coating to boost the intracellular uptake of the nanoparticles. The nanoparticles were characterized by TEM, dynamic light scattering, FTIR, and ultrasonic spectrometry. TEM revealed that the particles were ca. 6 nm in diameter, while FTIR showed that their surfaces were well-coated with PLL. The interaction of PLL-modified iron oxide nanoparticles with DMEM culture medium was verified by UV-vis spectroscopy. Rat bone marrow stromal cells (rMSCs) and human mesenchymal stem cells (hMSC) were labeled with PLL-modified iron oxide nanoparticles or with Endorem (control). Optical microscopy and TEM confirmed the presence of PLL-modified iron oxide nanoparticles inside the cells. Cellular uptake was very high (more than 92%) for PLL-modified nanoparticles that were coated with PLL (molecular weight 388 00) at a concentration of 0.02 mg PLL per milliliter of colloid. The cellular uptake of PLL-modified iron oxide was facilitated by its interaction with the negatively charged cell surface and subsequent endosomolytic uptake. The relaxivity of rMSCs labeled with PLL-modified iron oxide and the amount of iron in the cells were determined. PLL-modified iron oxide-labeled rMSCs were imaged in vitro and in vivo after intracerebral grafting into the contralateral hemisphere of the adult rat brain. The implanted cells were visible on magnetic resonance (MR) images as a hypointense area at the injection site and in the lesion. In comparison with Endorem, nanoparticles modified with PLL of an optimum molecular weight demonstrated a higher efficiency of intracellular uptake by MSC cells.

• MeSH
• adsorpce MeSH
• chemické jevy MeSH
• dextrany MeSH
• endocytóza účinky léků   MeSH
• fyzikální chemie MeSH
• krysa rodu Rattus MeSH
• kultivační média MeSH
• kultivované buňky MeSH
• lidé MeSH
• lysin chemie   MeSH
• magnetická rezonanční tomografie MeSH
• magnetické nanočástice MeSH
• magnetismus MeSH
• mezenchymální kmenové buňky účinky léků   ultrastruktura   MeSH
• mikroskopie elektronová rastrovací MeSH
• molekulová hmotnost MeSH
• nanočástice * MeSH
• oxid železnato-železitý MeSH
• oxidy chemie   MeSH
• polylysin chemie   MeSH
• proteiny chemie   MeSH
• spektroskopie infračervená s Fourierovou transformací MeSH
• transmisní elektronová mikroskopie MeSH
• transplantace kmenových buněk MeSH
• ultrazvuk MeSH
• velikost částic MeSH
• železité sloučeniny chemie   MeSH
• železo chemie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• dextrany MeSH
• ferric oxide MeSH Prohlížeč
• ferumoxides MeSH Prohlížeč
• kultivační média MeSH
• lysin MeSH
• magnetické nanočástice MeSH
• oxid železnato-železitý MeSH
• oxidy MeSH
• polylysin MeSH
• proteiny MeSH
• železité sloučeniny MeSH
• železo MeSH

Coprecipitation of FeCl2 and FeCl3 with aqueous ammonia was used to prepare iron oxide nanoparticles dispersible in aqueous medium. Oxidation of the particles with sodium hypochlorite then yielded maghemite (γ-Fe2 O3 ) nanoparticles which were coated with two types of coating -d-mannose or poly(l-lysine) (PLL) as confirmed by FTIR analysis. The particles were <10 nm according to transmission electron microscopy. Their hydrodynamic particle size was ∼180 nm (by dynamic light scattering). The d-mannose-, PLL-coated, and neat γ-Fe2 O3 particles as well as commercial Resovist® were used to label rat macrophages. The viability and contrast properties of labeled macrophages were compared. PLL-coated γ-Fe2 O3 nanoparticles were found optimal. The labeled macrophages were injected to rats monitored in vivo by magnetic resonance imaging up to 48 h. Transport of macrophages labeled with PLL-γ-Fe2 O3 nanoparticles in rats was confirmed. Tracking of macrophages using the developed particles can be used for monitoring of inflammations and cell migration in cell therapy.

• Klíčová slova
• MRI, iron oxide, labeling, macrophages, nanoparaticles,
• MeSH
• buněčný tracking metody   MeSH
• kontrastní látky * chemie   farmakologie   MeSH
• krysa rodu Rattus MeSH
• magnetická rezonanční tomografie metody   MeSH
• makrofágy diagnostické zobrazování   MeSH
• nanočástice chemie   MeSH
• polylysin * chemie   farmakologie   MeSH
• radiografie MeSH
• velikost částic MeSH
• železité sloučeniny * chemie   farmakologie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• ferric oxide MeSH Prohlížeč
• kontrastní látky * MeSH
• polylysin * MeSH
• železité sloučeniny * MeSH

Cells of Nicotiana tabacum L. cv. Wisconsin 38 were immobilized on poly (2,6-dimethyl)-p-phenyleneoxide in powder form (Sorfix) coated with poly-L-lysine (molecular weight 40 000 daltons). The dependence of cell immobilization on the amount of bound polyL-lysine was estimated.

• Publikační typ
• časopisecké články MeSH