Superparamagnetic iron oxide nanoparticles (SPION) with a "non-fouling" surface represent a versatile group of biocompatible nanomaterials valuable for medical diagnostics, including oncology. In our study we present a synthesis of novel maghemite (γ-Fe2O3) nanoparticles with positive and negative overall surface charge and their coating by copolymer P(HPMA-co-HAO) prepared by RAFT (reversible addition-fragmentation chain-transfer) copolymerization of N-(2-hydroxypropyl)methacrylamide (HPMA) with N-[2-(hydroxyamino)-2-oxo-ethyl]-2-methyl-prop-2-enamide (HAO). Coating was realized via hydroxamic acid groups of the HAO comonomer units with a strong affinity to maghemite. Dynamic light scattering (DLS) demonstrated high colloidal stability of the coated particles in a wide pH range, high ionic strength, and the presence of phosphate buffer (PBS) and serum albumin (BSE). Transmission electron microscopy (TEM) images show a narrow size distribution and spheroid shape. Alternative coatings were prepared by copolymerization of HPMA with methyl 2-(2-methylprop-2-enoylamino)acetate (MMA) and further post-polymerization modification with hydroxamic acid groups, carboxylic acid and primary-amino functionalities. Nevertheless, their colloidal stability was worse in comparison with P(HPMA-co-HAO). Additionally, P(HPMA-co-HAO)-coated nanoparticles were subjected to a bio-distribution study in mice. They were cleared from the blood stream by the liver relatively slowly, and their half-life in the liver depended on their charge; nevertheless, both cationic and anionic particles revealed a much shorter metabolic clearance rate than that of commercially available ferucarbotran.

• Klíčová slova
• MRI, contrast agents, hydroxamic acid, maghemite, non-fouling surface, polymer coating, superparamagnetic iron oxide nanoparticles,
• Publikační typ
• časopisecké články MeSH

Superporous poly(2-hydroxyethyl methacrylate-co-2-aminoethyl methacrylate) (P(HEMA-AEMA)) hydrogel scaffolds are designed for in vitro 3D culturing of leukemic B cells. Hydrogel porosity, which influences cell functions and growth, is introduced by adding ammonium oxalate needle-like crystals in the polymerization mixture. To improve cell vitality, cell-adhesive Arg-Gly-Asp-Ser (RGDS) peptide is immobilized on the N-(γ-maleimidobutyryloxy)succinimide-activated P(HEMA-AEMA) hydrogels via reaction of SH with maleimide groups. This modification is especially suitable for the survival of primary chronic lymphocytic leukemia cells (B-CLLs) in 3D cell culture. No other tested stimuli (interleukin-4, CD40 ligand, or shaking) can further improve B-CLL survival or metabolic activity. Both unmodified and RGDS-modified P(HEMA-AEMA) scaffolds serve as a long-term (70 days) 3D culture platforms for HS-5 and M2-10B4 bone marrow stromal cell lines and MEC-1 and HG-3 B-CLL cell lines, although the adherent cells retain their physiological morphologies, preferably on RGDS-modified hydrogels. Moreover, the porosity of hydrogels allows direct cell lysis, followed by efficient DNA isolation from the 3D-cultured cells. P(HEMA-AEMA)-RGDS thus serves as a suitable 3D in vitro leukemia model that enables molecular and metabolic assays and allows imaging of cell morphology, interactions, and migration by confocal microscopy. Such applications can prospectively assist in testing of drugs to treat this frequently recurring or refractory cancer.

• Klíčová slova
• 3D scaffold, B cell survival, RGDS, chronic lymphocytic leukemia, poly(2-hydroxyethyl methacrylate),
• MeSH
• buněčné kultury metody   MeSH
• chronická lymfatická leukemie * MeSH
• hydrogely chemie   MeSH
• lidé MeSH
• mezenchymální kmenové buňky MeSH
• nádorové buněčné linie MeSH
• oligopeptidy MeSH
• poréznost MeSH
• sukcinimidy chemie   MeSH
• tkáňové podpůrné struktury chemie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• arginyl-glycyl-aspartyl-serine MeSH Prohlížeč
• hydrogely MeSH
• N-(gamma-maleimidobutyryloxy)succinimide MeSH Prohlížeč
• oligopeptidy MeSH
• sukcinimidy MeSH

With the aim to develop a new anticancer agent, we prepared poly[N-(2-hydroxypropyl)methacrylamide-co-methyl 2-methacrylamidoacetate] [P(HP-MMAA)], which was reacted with hydrazine to poly[N-(2-hydroxypropyl)methacrylamide-co-N-(2-hydrazinyl-2-oxoethyl)methacrylamide] [P(HP-MAH)] to conjugate doxorubicin (Dox) via hydrazone bond. The resulting P(HP-MAH)-Dox conjugate was used as a coating of magnetic γ-Fe2 O3 nanoparticles obtained by the coprecipitation method. In vitro toxicity of various concentrations of Dox, P(HP-MAH)-Dox, and γ-Fe2 O3 @P(HP-MAH)-Dox nanoparticles was determined on somatic healthy cells (human bone marrow stromal cells hMSC), human glioblastoma line (GaMG), and primary human glioblastoma (GBM) cells isolated from GBM patients both at a short and prolonged exposition time (up to 7 days). Due to hydrolysis of the hydrazone bond in acid milieu of tumor cells and Dox release, the γ-Fe2 O3 @P(HP-MAH)-Dox nanoparticles significantly decreased the GaMG and GBM cell growth compared to free Dox and P(HP-MAH)-Dox in low concentration (10 nM), whereas in hMSCs it remained without effect. γ-F2 O3 @PHP nanoparticles alone did not affect the viability of any of the tested cells.

• Klíčová slova
• N-(2-hydroxypropyl)methacrylamide, cancer treatment, doxorubicin, iron oxide, magnetic,
• MeSH
• akrylamidy chemie   MeSH
• doxorubicin chemie   metabolismus   farmakologie   MeSH
• glioblastom patologie   MeSH
• lidé MeSH
• magnetické nanočástice chemie   MeSH
• nádorové buněčné linie MeSH
• nosiče léků chemie   MeSH
• polymery chemie   MeSH
• proliferace buněk MeSH
• protinádorové látky chemie   metabolismus   farmakologie   MeSH
• regulace genové exprese u nádorů účinky léků   MeSH
• uvolňování léčiv MeSH
• viabilita buněk účinky léků   MeSH
• železité sloučeniny chemie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• akrylamidy MeSH
• doxorubicin MeSH
• ferric oxide MeSH Prohlížeč
• magnetické nanočástice MeSH
• N-(2-hydroxypropyl)methacrylamide MeSH Prohlížeč
• nosiče léků MeSH
• polymery MeSH
• protinádorové látky MeSH
• železité sloučeniny MeSH

Doxorubicin-conjugated magnetic nanoparticles containing hydrolyzable hydrazone bonds were developed using a non-toxic poly[N-(2-hydroxypropyl)methacrylamide] (PHPMA) coating, which ensured good colloidal stability in aqueous media and limited internalization by the cells, however, enabled adhesion to the cell surface. While the neat PHPMA-coated particles proved to be non-toxic, doxorubicin-conjugated particles exhibited enhanced cytotoxicity in both drug-sensitive and drug-resistant tumor cells compared to free doxorubicin. The newly developed doxorubicin-conjugated PHPMA-coated magnetic particles seem to be a promising magnetically targeted vehicle for anticancer drug delivery.

• Klíčová slova
• cytotoxicity, doxorubicin, magnetic, nanoparticles, poly[N-(2-hydroxypropyl)methacrylamide],
• Publikační typ
• časopisecké články MeSH

Degradable poly(2-hydroxyethyl methacrylate) hydrogels were prepared from a linear copolymer (Mw = 49 kDa) of 2-hydroxyethyl methacrylate (HEMA), 2-(acethylthio)ethyl methacrylate (ATEMA), and zwitterionic 2-methacryloyloxyethyl phosphorylcholine (MPC). The deprotection of ATEMA thiol groups by triethylamine followed by their gentle oxidation with 2,2'-dithiodipyridine resulted in the formation of reductively degradable polymers with disulfide bridges. Finally, a hydrogel 3D structure with an oriented porosity was obtained by gelation of the polymer in the presence of needle-like sodium acetate crystals. The pore diameter and porosity of resulting poly(2-hydroxyethyl methacrylate-co-2-(acethylthio)ethyl methacrylate-co-2-methacryloyloxyethyl phosphorylcholine) [P(HEMA-ATEMA-MPC)] hydrogels varied between 59 and 65 μm and between 70 and 79.6 vol % according to Hg porosimetry, and complete degradation of these materials was reached in 86 days in 0.33 mmol solution of l-cysteine/L in phosphate buffer. The cross-linked P(HEMA-ATEMA-MPC) hydrogels were evaluated as a possible support for human mesenchymal stem cells (MSCs). No cytotoxicity was found for the un-cross-linked thiol-containing and protected P(HEMA-ATEMA-MPC) chains up to a concentration of 5 and 1 wt % in α-minimum essential medium, respectively.

• Klíčová slova
• 2-(acethylthio)ethyl methacrylate, 2-methacryloyloxyethyl phosphorylcholine, hydrogel, oriented porosity, poly(2-hydroxyethyl methacrylate), reductively degradable,
• MeSH
• hydrogely MeSH
• lidé MeSH
• polyhydroxyethylmethakrylát chemie   MeSH
• poréznost MeSH
• tkáňové inženýrství MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• hydrogely MeSH
• polyhydroxyethylmethakrylát MeSH

Three-dimensional hydrogel supports for mesenchymal and neural stem cells (NSCs) are promising materials for tissue engineering applications such as spinal cord repair. This study involves the preparation and characterization of superporous scaffolds based on a copolymer of 2-hydroxyethyl and 2-aminoethyl methacrylate (HEMA and AEMA) crosslinked with ethylene dimethacrylate. Ammonium oxalate is chosen as a suitable porogen because it consists of needle-like crystals, allowing their parallel arrangement in the polymerization mold. The amino group of AEMA is used to immobilize RGDS and SIKVAVS peptide sequences with an N-γ-maleimidobutyryloxy succinimide ester linker. The amount of the peptide on the scaffold is determined using 125 I radiolabeled SIKVAVS. Both RGDS- and SIKVAVS-modified poly(2-hydroxyethyl methacrylate) scaffolds serve as supports for culturing human mesenchymal stem cells (MSCs) and human fetal NSCs. The RGDS sequence is found to be better for MSC and NSC proliferation and growth than SIKVAVS.

• Klíčová slova
• IKVAV, RGD, peptide, poly(2-hydroxyethyl methacrylate), stem cell,
• MeSH
• buněčné linie MeSH
• lidé MeSH
• methylmetakryláty chemie   farmakologie   MeSH
• mezenchymální kmenové buňky cytologie   MeSH
• nervové kmenové buňky cytologie   metabolismus   MeSH
• oligopeptidy * chemie   farmakologie   MeSH
• tkáňové inženýrství metody   MeSH
• tkáňové podpůrné struktury chemie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• arginyl-glycyl-aspartyl-serine MeSH Prohlížeč
• hydroxymethylmethacrylate MeSH Prohlížeč
• methylmetakryláty MeSH
• oligopeptidy * MeSH
• seryl-isoleucyl-lysyl-valyl-alanyl-valinamide MeSH Prohlížeč

Molecular diagnostics may provide tailored and cost efficient treatment for infectious disease and cancer. Rolling circle amplification (RCA) of padlock probes guarantees high specificity to identify nucleic acid targets down to single nucleotide resolution in a multiplex fashion. This makes the assay suitable for molecular analysis of various diseases, and interesting to integrate into automated devices for point-of-care analysis. A critical prerequisite for many molecular assays is (i) target-specific isolation from complex clinical samples and (ii) removal of reagents, inhibitors and contaminants between reaction steps. Efficient solid supports are therefore essential to enable multi-step, multi-analyte protocols. Superparamagnetic micro- and nanoparticles, with large surface area and rapid liquid-phase kinetics, are attractive for multi-step protocols. Recently, streptavidin-modified magnetic monodispersed poly(2-hydroxyethyl methacrylate) (STV-mag.PHEMA) microspheres were developed by multiple swelling polymerization. They are easily separated by a magnet and exhibit low non-specific protein sorption. In this study, the performance and the binding efficiency of STV-mag.PHEMA was addressed by circle-to-circle amplification (C2CA). A lower number of RCA products were detected as compared to the gold standard Dynabeads. Nevertheless, this study was the first to successfully adapt STV-mag.PHEMA microspheres as solid support in a DNA-based protocol, which is an important finding. The STV-mag.PHEMA microspheres were larger with about 16 times less surface area as compared to the Dynabeads, which might partly explain the lower rolling circle product (RCP) count obtained. Further research is currently ongoing comparing particles of similar sizes and optimizing reaction conditions to establish their full utility in the field. Ultimately, low cost and versatile particles are a great resource to facilitate future clinical molecular diagnostics.

• Klíčová slova
• DNA, Magnetic microspheres, Poly(2-hydroxyethyl methacrylate), Rolling circle amplification,
• MeSH
• DNA chemie   metabolismus   MeSH
• imobilizované proteiny chemie   metabolismus   MeSH
• magnetismus MeSH
• mikrosféry * MeSH
• mikroskopie elektronová rastrovací MeSH
• polyhydroxyethylmethakrylát chemie   MeSH
• spektroskopie infračervená s Fourierovou transformací MeSH
• streptavidin chemie   metabolismus   MeSH
• techniky amplifikace nukleových kyselin MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• DNA MeSH
• imobilizované proteiny MeSH
• polyhydroxyethylmethakrylát MeSH
• streptavidin MeSH

The architecture and mechanical properties of a scaffold for spinal cord injury treatment must provide tissue integration as well as effective axonal regeneration. Previous work has demonstrated the cell-adhesive and growth-promoting properties of the SIKVAV (Ser-Ile-Lys-Val-Ala-Val)-modified highly superporous poly(2-hydroxethyl methacrylate) (PHEMA) hydrogels. The aim of the current study was to optimize the porosity and mechanical properties of this type of hydrogel in order to develop a suitable scaffold for the repair of spinal cord tissue. Three types of highly superporous PHEMA hydrogels with oriented pores of ~60 µm diameter, porosities of 57-68% and equivalent stiffness characterized by elasticity moduli in the range 3-45 kPa were implanted into a spinal cord hemisection, and their integration into the host tissue, as well as the extent of axonal ingrowth into the scaffold pores, were histologically evaluated. The best tissue response was found with a SIKVAV-modified PHEMA hydrogel with 68% porosity and a moderate modulus of elasticity (27 kPa in the direction along the pores and 3.6 kPa in the perpendicular direction). When implanted into a spinal cord transection, the hydrogel promoted tissue bridging as well as aligned axonal ingrowth. In conclusion, a prospective oriented scaffold architecture of SIKVAV-modified PHEMA hydrogels has been developed for spinal cord injury repair; however, to develop an effective treatment for spinal cord injury, multiple therapeutic approaches are needed.

• Klíčová slova
• 2-hydroxyethyl methacrylate, IKVAV (Ile-Lys-Val-Ala-Val) peptide, hydrogel, oriented pores, scaffold, spinal cord repair,
• MeSH
• axony patologie   MeSH
• biokompatibilní materiály chemie   MeSH
• hojení ran MeSH
• hydrogely chemie   MeSH
• krysa rodu Rattus MeSH
• mechanický stres MeSH
• mezenchymální kmenové buňky cytologie   MeSH
• mikroskopie elektronová rastrovací MeSH
• oligopeptidy chemie   MeSH
• polyhydroxyethylmethakrylát chemie   MeSH
• poranění míchy rehabilitace   terapie   MeSH
• poréznost MeSH
• potkani Wistar MeSH
• pružnost MeSH
• regenerace nervu MeSH
• tkáňové inženýrství metody   MeSH
• tkáňové podpůrné struktury chemie   MeSH
• tlak MeSH
• zelené fluorescenční proteiny chemie   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
• biokompatibilní materiály MeSH
• hydrogely MeSH
• oligopeptidy MeSH
• polyhydroxyethylmethakrylát MeSH
• seryl-isoleucyl-lysyl-valyl-alanyl-valinamide MeSH Prohlížeč
• zelené fluorescenční proteiny MeSH

A nanobiosensor based on the use of porous magnetic microspheres (PMM) as efficient capturing/pre-concentrating platform is presented for detection of Alzheimer's disease (AD) biomarkers. These PMMs prepared by a multistep swelling polymerization combined with iron oxide precipitation afford carboxyl functional groups suitable for immobilization of antibodies on the particle surface allowing an enhanced efficiency in the capturing of AD biomarkers from human serum samples. The AD biomarkers signaling is produced by gold nanoparticle (AuNP) tags monitored through their electrocatalytic effect towards hydrogen evolution reaction (HER). Novel properties of PMMs in terms of high functionality and high active area available for enhanced catalytic activity of the captured AuNPs electrocatalytic tags are exploited for the first time. A thorough characterization by scanning transmission electron microscope in high angle annular dark field mode (STEM-HAADF) demonstrates the enhanced ability of PMMs to capture a higher quantity of analyte and consequently of electrocatalytic label, when compared with commercially available microspheres. The optimized and characterized PMMs are also applied for the first time for the detection of beta amyloid and ApoE at clinical relevant levels in cerebrospinal fluid (CSF), serum and plasma samples of patients suffering from AD.

• Klíčová slova
• Alzheimer disease biomarker, Electrochemical immunoassay, Gold nanoparticles, Hydrogen evolution reaction, Porous magnetic microspheres,
• MeSH
• Alzheimerova nemoc diagnóza   metabolismus   MeSH
• amyloidní beta-protein analýza   MeSH
• apolipoproteiny E analýza   MeSH
• barvení a značení MeSH
• biologické markery analýza   MeSH
• imunomagnetická separace metody   MeSH
• katalýza MeSH
• konduktometrie metody   MeSH
• kovové nanočástice chemie   ultrastruktura   MeSH
• lidé MeSH
• mikrosféry MeSH
• poréznost MeSH
• reprodukovatelnost výsledků MeSH
• senzitivita a specificita MeSH
• zlato chemie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• amyloidní beta-protein MeSH
• apolipoproteiny E MeSH
• biologické markery MeSH
• zlato MeSH

The efficient isolation and concentration of protein antigens from complex biological samples is a critical step in several analytical methods, such as mass spectrometry, flow cytometry and immunochemistry. These techniques take advantage of magnetic microspheres as immunosorbents. The focus of this study was on the development of new superparamagnetic polymer microspheres for the specific isolation of the tumor suppressor protein p53. Monodisperse macroporous poly(glycidyl methacrylate) (PGMA) microspheres measuring approximately 5 μm and containing carboxyl groups were prepared by multistep swelling polymerization of glycidyl methacrylate (GMA), 2-[(methoxycarbonyl)methoxy]ethyl methacrylate (MCMEMA) and ethylene dimethylacrylate (EDMA) as a crosslinker in the presence of cyclohexyl acetate as a porogen. To render the microspheres magnetic, iron oxide was precipitated within their pores; the Fe content in the particles received ∼18 wt%. Nonspecific interactions between the magnetic particles and biological media were minimized by coating the microspheres with poly(ethylene glycol) (PEG) terminated by carboxyl groups. The carboxyl groups of the magnetic PGMA microspheres were conjugated with primary amino groups of mouse monoclonal DO-1 antibody using conventional carbodiimide chemistry. The efficiency of protein p53 capture and the degree of nonspecific adsorption on neat and PEG-coated magnetic microspheres were determined by western blot analysis.

• MeSH
• kyseliny polymethakrylové chemie   MeSH
• mikrosféry * MeSH
• myší monoklonální protilátky chemie   MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• nádorový supresorový protein p53 chemie   izolace a purifikace   MeSH
• polyethylenglykoly chemie   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• kyseliny polymethakrylové MeSH
• myší monoklonální protilátky MeSH
• nádorový supresorový protein p53 MeSH
• polyethylenglykoly MeSH
• polyglycidyl methacrylate MeSH Prohlížeč