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.

• Keywords
• DNA, EcoRI, Enzymatic restriction, Microparticles, Poly(methacrylic acid-co-ethylene dimethacrylate), Solid phase extraction,
• MeSH
• DNA, Bacterial chemistry   isolation & purification   MeSH
• DNA chemistry   isolation & purification   MeSH
• Solid Phase Extraction * methods   MeSH
• Hydrophobic and Hydrophilic Interactions MeSH
• Hydrogen-Ion Concentration MeSH
• Polymers chemistry   MeSH
• Polymethyl Methacrylate chemistry   MeSH
• Particle Size MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• DNA, Bacterial MeSH
• DNA MeSH
• poly(MAA-co-EDMA) MeSH Browser
• Polymers MeSH
• Polymethyl Methacrylate MeSH

Poly(glycidyl methacrylate) (PGMA) is prone to modifications with different functional groups, magnetic fluids or direct coupling with biological molecules. The purpose of this research was to synthesize new magnetically responsive particles with peroxidase-like activity. Poly(glycidyl methacrylate-co-ethylene dimethacrylate) [P(GMA-EDMA)] particles containing carboxyl groups were obtained by emulsifier-free emulsion polymerization and hydrolysis and oxidation of PGMA with KMnO4, resulting in poly(carboxymethyl methacrylate-co-ethylene dimethacrylate) [P(CMMA-EDMA)] particles. Thionine (Th) was also attached to the particles [(P(CMMA-EDMA)-Th] via EDC/NHS chemistry to observe its effect on electron transfer during the oxidation reaction. Finally, the particles were coated with a nitric acid-stabilized ferrofluid in methanol. The resulting magnetic particles were characterized by several methods, including scanning and transmission electron microscopy, X-ray photoelectron spectroscopy, and vibrating sample magnetometry. The effect of EDMA on the P(CMMA-EDMA) particle size and size distribution was investigated; the particle size changed from 300 to 340 nm, and the particles were monodispersed with a saturation magnetization of 11 Am2/kg. Finally, the effects of temperature and pH on the peroxidase-like activity of the magnetic P(CMMA-EDMA) and P(CMMA-EDMA)-Th particles were investigated. The particles, which exhibited a high activity at pH 4-6 and at ∼37 °C, represent a highly sensitive sensor component potentially useful in enzyme-based immunoassays.

• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't 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.

• Keywords
• cytotoxicity, doxorubicin, magnetic, nanoparticles, poly[N-(2-hydroxypropyl)methacrylamide],
• Publication type
• Journal Article MeSH

Magnetic particles (MPs) have been widely used in biological applications in recent years as a carrier for various molecules. Their big advantage is in repeated use of immobilized molecules including enzymes. Acetylcholinesterase (AChE) is an enzyme playing crucial role in neurotransmission and the enzyme is targeted by various molecules like Alzheimer's drugs, pesticides and warfare agents. In this work, an electrochemical biosensor having AChE immobilized onto MPs and stabilized through glutaraldehyde (GA) molecule was proposed for assay of the neurotoxic compounds. The prepared nanoparticles were modified by pure AChE and they were used for the measurement anti-Alzheimer's drug galantamine and carbamate pesticide carbofuran with limit of detection 1.5 µM and 20 nM, respectively. All measurements were carried out using screen-printed sensor with carbon working, silver reference, and carbon auxiliary electrode. Standard Ellman's assay was used for validation measurement of both inhibitors. Part of this work was the elimination of reversible inhibitors represented by galantamine from the active site of AChE. For this purpose, we used a lower pH to get the original activity of AChE after inhibition by galantamine. We also observed decarbamylation of the AChE-carbofuran adduct. Influence of organic solvents to AChE as well as repeatability of measurement with MPs with AChE was also established.

• Keywords
• acetylcholinesterase, carbofuran, electrochemistry, galantamine, magnetic particles, nanomaterial, nanoparticles, screen-printed sensor,
• MeSH
• Acetylcholinesterase MeSH
• Biosensing Techniques MeSH
• Cholinesterase Inhibitors MeSH
• Enzymes, Immobilized MeSH
• Nanoparticles * MeSH
• Organophosphorus Compounds MeSH
• Pesticides MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Acetylcholinesterase MeSH
• Cholinesterase Inhibitors MeSH
• Enzymes, Immobilized MeSH
• Organophosphorus Compounds MeSH
• Pesticides MeSH

Sodium hyaluronate (HA) was associated with dopamine (DPA) and introduced as a coating for maghemite (γ-Fe(2)O(3)) nanoparticles obtained by the coprecipitation of iron(II) and iron(III) chlorides and oxidation with sodium hypochlorite. The effects of the DPA anchorage of HA on the γ-Fe(2)O(3) surface on the physicochemical properties of the resulting colloids were investigated. Nanoparticles coated at three different DPA-HA/γ-Fe(2)O(3) and DPA/HA ratios were chosen for experiments with rat bone marrow mesenchymal stem cells and human chondrocytes. The nanoparticles were internalized into rat bone marrow mesenchymal stem cells via endocytosis as confirmed by Prussian Blue staining. The efficiency of mesenchymal stem cell labeling was analyzed. From among the investigated samples, efficient cell labeling was achieved by using DPA-HA-γ-Fe(2)O(3) nanoparticles with DPA-HA/γ-Fe(2)O(3) = 0.45 (weight/ weight) and DPA/HA = 0.038 (weight/weight) ratios. The particles were used as a contrast agent in magnetic resonance imaging for the labeling and visualization of cells.

• Keywords
• cell labeling, dopamine, hyaluronate, magnetic, nanoparticles,
• MeSH
• Coated Materials, Biocompatible chemistry   MeSH
• Cell Differentiation MeSH
• Chondrocytes cytology   MeSH
• Dopamine chemistry   MeSH
• Endocytosis MeSH
• Ferrocyanides MeSH
• Contrast Media MeSH
• Rats MeSH
• Cells, Cultured MeSH
• Hyaluronic Acid chemistry   MeSH
• Humans MeSH
• Magnetic Resonance Imaging MeSH
• Magnetite Nanoparticles chemistry   ultrastructure   MeSH
• Mesenchymal Stem Cells cytology   drug effects   MeSH
• Nanomedicine MeSH
• Microscopy, Electron, Transmission MeSH
• Particle Size MeSH
• Cell Survival MeSH
• Animals MeSH
• Check Tag
• Rats MeSH
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Coated Materials, Biocompatible MeSH
• Dopamine MeSH
• ferric ferrocyanide MeSH Browser
• Ferrocyanides MeSH
• Contrast Media MeSH
• Hyaluronic Acid MeSH
• Magnetite Nanoparticles MeSH