Heterogeneous radical polymerizations include several polymerization techniques allowing to prepare polymer particles from various vinyl monomers. These polymerizations, namely suspension, dispersion, precipitation, and emulsion polymerization, as well as swelling techniques, have been widely used for the lab- and industrial-scale preparation of important polymers, for example polystyrene, poly(styrene-co-divinylbenzene), poly(vinyl acetate), poly(vinyl chloride), polymethacrylates. Typical characteristics of each of the polymerizations predetermine a selection of monomer, initiator, solvent, stabilization, and define the final particle size, particle size distribution, and particle morphology. On the other hand, they also limit the utilization of the given polymerization. In the first part of the review, the basic polymerization techniques for the preparation of microparticles were described. The second part of the review is dedicated to the fundamental theoretical and practical features and specific aspects of emulsion polymerizations, which are used for the preparation of various polymer particles having their size in the nano­meter range.

Horseradish peroxidase (HRP)/H2O2-mediated crosslinking of polypeptides in inverse miniemulsion is a promising approach for the development of next-generation biocompatible and biodegradable nanogels. Herein, we present a fundamental investigation of the effects of three surfactants and their different concentrations on the (HRP)/H2O2-mediated nanogelation of poly[N5-(2-hydroxyethyl)-l-glutamine-ran-N5-propargyl-l-glutamine-ran-N5-(6-aminohexyl)-l-glutamine]-ran-N5-[2-(4-hydroxyphenyl)ethyl)-l-glutamine] (PHEG-Tyr) in inverse miniemulsion. The surfactants sorbitan monooleate (SPAN 80), polyoxyethylenesorbitan trioleate (TWEEN 85), and dioctyl sulfosuccinate sodium salt (AOT) were selected and their influence on the nanogel size, size distribution, and morphology was evaluated. The most effective nanogelation stabilization was achieved with 20 wt% nonionic surfactant SPAN 80. The diameter of the hydrogel nanoparticles was 230 nm (dynamic light scattering, DLS) and was confirmed also by nanoparticle tracking analysis (NTA) which showed the diameters ranging from 200 to 300 nm. Microscopy and image analyses showed that the nanogel in the dry state was spherical in shape and had number-average diameter Dn = 26 nm and dispersity Р= 1.91. In the frozen-hydrated state, the nanogel appeared porous and was larger in size with Dn = 182 nm and Р= 1.52. Our results indicated that the nanogelation of the polymer precursor required a higher concentration of surfactant than classical inverse miniemulsion polymerization to ensure effective stabilization. The developed polypeptide nanogel was radiolabeled with 125I, and in vivo biodistribution and blood clearance evaluations were performed. We found that the 125I-labeled nanogel was well-biodistributed in the bloodstream, cleared from mouse blood during 48 h by renal and hepatic pathways and did not provoke any sign of toxic effects.

• MeSH
• myši MeSH
• nanogely MeSH
• peptidy MeSH
• peroxid vodíku * MeSH
• polyethylenglykoly MeSH
• polyethylenimin MeSH
• povrchově aktivní látky * MeSH
• tkáňová distribuce MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

The efficiency of solid phase extraction (SPE) of DNA on polymer particles is limited by the features of the applied solid support, such as size, hydrophilicity, and functionality and their application in SPE also requires additional steps and compounds to finally obtain sufficient amount of high-quality DNA. The present study describes a preparation of sub-micrometer monodisperse poly(methacrylic acid-co-ethylene dimethacrylate) (PME) particles by precipitation polymerization. The effect of the ethylene dimethacrylate (EDMA) crosslinker concentration on morphology and particle size, which varied from 730 to 900 nm, was investigated. The particles with 5 and 15 wt% EDMA were selected for a study of SPE of plasmid DNA under various adsorption and elution conditions, followed by the enzymatic restriction of isolated DNA to verify a quality the nucleic acid. The particles with 15 wt% EDMA were suitable for the SPE because they retained better colloidal stability during the adsorption without additional induction of DNA conformational change. The quality of isolated DNA was finally verified by enzymatic restriction by restriction endonuclease EcoRI. Moreover, the developed method using PME particles was successfully utilized for DNA isolation from Escherichia coli lysate.

• MeSH
• DNA bakterií chemie   izolace a purifikace   MeSH
• DNA chemie   izolace a purifikace   MeSH
• extrakce na pevné fázi * metody   MeSH
• hydrofobní a hydrofilní interakce MeSH
• koncentrace vodíkových iontů MeSH
• polymery chemie   MeSH
• polymethylmethakrylát chemie   MeSH
• velikost částic MeSH
• Publikační typ
• časopisecké články MeSH

A very simple and readily performed method is described for the preparation of poly(styrene-divinylbenzene-methacrylic acid) monolithic columns for capillary liquid chromatography. The effect of the methacrylic acid content on the morphological and chromatographic properties has been investigated. Methacrylic acid is shown to be essential for isocratic separations of small organic analytes by capillary liquid chromatography. Column efficiencies of about 28,000 theoretical plates/m have been obtained for all the test compounds. The batch-to-batch and run-to-run repeatability of the retention times is better than 1.5%.

• MeSH
• chromatografie kapalinová metody   MeSH
• methakryláty chemie   MeSH
• polymery chemie   MeSH
• styren chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH