Encontrados 111 documentos, a visualizar página 1 de 12

Cloning expression and characterization of a chitin-binding domain

Chitosan and chitin represent a family of biopolymers, made up of β(1 → 4)-linked N-acetyl-d-glucosamine and d-glucosamine subunits. Chitin can be found in exoskeletons of insects, fungal cell walls and shells of crustaceans and is one of the most abundant natural polysaccharides in nature, second only to cellulose. On the other hand, chitosan is mainly obtained industrially by alkaline hydrolysis of chitin (Ts...

New dextrin nanomagnetogels as contrast agents for magnetic resonance imaging

This study aims at the production and characterization of a “nanomagnetogel” consisting of superparamagnetic iron oxide nanoparticles (g-Fe2O3) stabilized within a hydrophobized-dextrin nanogel. The nanomagnetogel obtained was extensively characterized with respect to physico-chemical (transmission electron microscopy, cryo-scanning electron microscopy, dynamic light scattering, small angle X-ray scattering), m...

Polymeric nanogels as vaccine delivery systems

Polymeric nanogels find a relevant field of application in the formulation of a new generation of therapeutic and preventive vaccines, aiming at the fine-tuned modulation of the immune response. Intrinsic properties of polymeric nanogels, such as material chemistry, size and shape, surface charge, and hydrophobicity or hydrophilicity, may be determining factors in shaping the induced immune response. These mate...

Recombinant expression and purification of the antimicrobial peptide Magainin-2

Magainin-2 (MAG2) is a polycationic antimicrobial peptide isolated from the skin of the African clawed frog Xenopus laevis. It has a wide spectrum of antimicrobial activities against Gram-positive and Gram-negative bacteria, fungi and induces osmotic lysis of protozoa. MAG2 also possesses antiviral and antitumoral properties. These activities make this peptide a promising candidate for therapeutic applications....

Biocompatibility of poly(lactic acid) with incorporated graphene-based materials

The incorporation of graphene-based materials has been shown to improve mechanical properties of poly(lactic acid) (PLA). In this work, PLA films and composite PLA films incorporating two graphene-based materials – graphene oxide (GO) and graphene nanoplatelets (GNP) – were prepared and characterized regarding not only biocompatibility, but also surface topography, chemistry and wettability. The presence of bot...

Production and characterization of a new bacterial cellulose/poly(vinyl alcohol...

Bacterial cellulose (BC) is characterized for its high water holding capacity, high crystallinity, an ultrafine fiber network and high tensile strength. This work demonstrates the production of a new interpenetrated polymer network nanocomposite obtained through the incorporation of poly(vinyl alcohol) (PVA) on the BC matrix and evaluates the effect of oven drying on the morphological, mechanical and mass trans...

Hemocompatibility study of a bacterial cellulose/polyvinyl alcohol nanocomposite

Bacterial cellulose (BC) has been suggested to be a suitable biomaterial for the development of cardiovascular grafts. The combination of BC with polyvinyl alcohol (PVA) results in nanocomposites with improved properties. Surprisingly, there are very few studies on the BC–blood interaction. This is the focus of this paper. We present the first thorough assessment of the hemocompatibility of the BC/PVA nanocompo...

Glycol chitosan-based nanogel as a potential targetable carrier for siRNA

A self-assembled glycol chitosan nanogel (GC) is synthesized by chemically grafting hydrophobic chains onto a polysaccharide, which is comprehensively characterized. The obtained macromolecular micelle is decorated with folate-conjugated poly(ethylene glycol) (PEG) (GCFA). An average size distribution of 250 and 200 nm is observed, respectively for the GC and GCFA nanogels. Differential cell localization is obs...

New dextrin nanomagnetogels as contrast agents for magnetic resonance imaging

This study aims at the production and characterization of a “nanomagnetogel” consisting of superparamagnetic iron oxide nanoparticles (γ-Fe2O3) stabilized within a hydrophobized-dextrin nanogel. The nanomagnetogel obtained was extensively characterized with respect to physico-chemical (transmission electron microscopy, cryo-scanning electron microscopy, dynamic light scattering, small angle X-ray scattering), m...

Cloning and expression of Clostridium thermocellum CBM3 in Pichia pastoris