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1.
Bioprocess Biosyst Eng ; 43(7): 1279-1286, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32189054

ABSTRACT

In this work, the free lipase Eversa® Transform 2.0 was used as a catalyst for enzymatic glycerolysis reaction in a solvent-free system. The product was evaluated by nuclear magnetic resonance (1H NMR) and showed high conversion related to hydroxyl groups. In sequence, the product of the glycerolysis was used as stabilizer and biopolyol for the synthesis of poly(urea-urethane) nanoparticles (PUU NPs) aqueous dispersion by the miniemulsion polymerization technique, without the use of a further surfactant in the system. Reactions resulted in stable dispersions of PUU NPs with an average diameter of 190 nm. After, the formation of the PUU NPs in the presence of concentrated lipase Eversa® Transform 2.0 was studied, aiming the lipase immobilization on the NP surface, and a stable enzymatic derivative with diameters around 231 nm was obtained. The hydrolytic enzymatic activity was determined using ρ-nitrophenyl palmitate (ρ-NPP) and the immobilization was confirmed by morphological analysis using transmission electron microscopy and fluorescence microscopy.


Subject(s)
Enzymes, Immobilized/immunology , Glycerol/chemistry , Lipase/metabolism , Polymers/chemistry , Polyurethanes/chemistry , Microscopy, Electron, Transmission , Sonication , Spectroscopy, Fourier Transform Infrared
2.
Pharm Dev Technol ; 24(5): 593-599, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30457422

ABSTRACT

The current paucity of effective and affordable drugs for the treatment of leishmaniasis renders the search for new therapeutic alternatives a priority. Gallic acid-related compounds display anti-parasitic activities and their incorporation into drug carrier systems, such as polymeric nanoparticles may be a viable alternative for leishmaniasis treatment. Therefore, this study focused on the synthesis and characterization of octyl gallate (G8) loaded poly(methyl methacrylate) (PMMA) nanoparticles via miniemulsion polymerization in order to increase the leishmanicidal activity of this compound. G8 loaded PMMA nanoparticles presented a spherical morphology with a mean size of 108 nm, a negatively charged surface (-33 ± 5 mV) and high encapsulation efficiency (83% ± 5). Fourier-transform infrared spectroscopy and X-ray diffraction analysis confirmed that G8 was encapsulated in PMMA nanoparticles and presented a biphasic release profile. The G8 loaded PMMA nanoparticles did not present cytotoxic effect on human red blood cells. G8 loaded PMMA nanoparticles displayed a leishmanicidal activity almost three times higher than free G8 while the cytotoxic activity against human THP-1 cells remained unchanged.


Subject(s)
Drug Carriers/chemistry , Gallic Acid/analogs & derivatives , Leishmania/drug effects , Polymethyl Methacrylate/chemistry , Trypanocidal Agents/administration & dosage , Trypanocidal Agents/pharmacology , Caco-2 Cells , Cell Line , Drug Liberation , Emulsions/chemistry , Gallic Acid/administration & dosage , Gallic Acid/chemistry , Gallic Acid/pharmacology , Hemolysis/drug effects , Humans , Leishmaniasis/drug therapy , Nanoparticles/chemistry , Nanoparticles/ultrastructure , Trypanocidal Agents/chemistry
3.
Colloids Surf B Biointerfaces ; 135: 357-364, 2015 Nov 01.
Article in English | MEDLINE | ID: mdl-26263221

ABSTRACT

The aim of this work was the simultaneous encapsulation of magnetic nanoparticles (MNPs) and zinc(II) phthalocyanine (ZnPc) in poly(methyl methacrylate) (PMMA) (MNPsZnPc-PMMA) nanoparticles (NPs) by miniemulsion polymerization and to evaluate the photobiological activity and/or hyperthermia (HPT) against human glioblastoma cells (U87MG). MNPsZnPc-PMMA NPs presented an average diameter of 104 ± 2.5 nm with a polydispersity index (PdI) of 0.14 ± 0.03 and negative surface charge - 47 ± 2.2 mV (pH 7.4 ± 0.1). The encapsulation efficiency (EE%) of ZnPc was 85.7% ± 1.30. The release of ZnPc from PMMA NPs was slow and sustained without the presence of burst effect, indicating a homogeneous distribution of the drug in the polymeric matrix. In the biological assay, MNPsZnPc-PMMA NPs showed considerable cytotoxic effect on U87MG cells only after activation with visible light at 675 nm (photodynamic therapy, PDT) or after application of an alternating magnetic field. The simultaneous encapsulation of MNPs and ZnPc in a drug delivery system with sustained release can be a new alternative for cancer treatment leading to significant tumor regression after minimum doses of heat dissipation and light.


Subject(s)
Indoles/chemistry , Nanoparticles/chemistry , Organometallic Compounds/chemistry , Polymethyl Methacrylate/chemistry , Antineoplastic Agents/administration & dosage , Cell Line, Tumor , Cell Survival/drug effects , Delayed-Action Preparations , Drug Compounding , Drug Delivery Systems , Emulsions , Humans , Isoindoles , Light , Magnetic Fields , Magnetite Nanoparticles , Nanoparticles/radiation effects , Polymerization , Zinc Compounds
4.
Colloids Surf B Biointerfaces ; 135: 35-41, 2015 Nov 01.
Article in English | MEDLINE | ID: mdl-26241914

ABSTRACT

In this work biocompatible polyurethane nanoparticles for future application as noninvasive polymeric nanocarriers using propellant-based inhalers in the treatment of respiratory diseases were prepared by miniemulsion interfacial polymerization derived from isophorone diisocyanate, poly(ϵ-caprolactone), and poly(ethylene glycol). The effects of the surfactant type, nonionic Tween 80 and Brij 35, anionic sodium dodecyl sulfate, and cationic cetyltrimethyl ammonium bromide, and poly(ethylene glycol) molar mass on the stability, size and morphology of nanoparticles were evaluated. In addition, the ability of cells to proliferate in contact with polyurethane nanoparticles was assessed by MTS ([(3-(4,5-dimethylthiazole-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfo-phenyl)-2H-tetrazolium, inner salt]) assay using human lung adenocarcinoma A549 cells, an in vitro model of Type II alveolar epithelium.


Subject(s)
Nanoparticles/chemistry , Polyesters/chemistry , Polyethylene Glycols/chemistry , Polyurethanes/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Drug Stability , Emulsions , Epithelial Cells/drug effects , Humans , Molecular Weight , Particle Size , Polymerization , Surface-Active Agents
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