Search

In recent years a great interest in the study of the association of magnetic with biological material for bioapplications has been observed in the literature. This work analyses the development of new magnetic biocomposite films from a magnetic ferrite and a biopolymer. Magnetic and dielectric properties of Y3Fe5O12 (YIG)/collagen composite films were studied as a function of the YIG concentration. This biocomposite was also characterized by Infrared Spectroscopy (IR), Thermal Analysis (DSC and TG) and scanning electron microspcopic (SEM) methods. The magnetization and dielectric measurements were performed at room temperature. The results demonstrated that ferrimagnetic garnet (YIG) and collagen (Col) can be used to obtain a homogeneous composite. All the composite films showed a ferromagnetic behavior and they were characterized as a soft magnet material. These results show that Col-YIG biocomposites are biological films with magnetic properties that can be employed as a versatile performance materials, due to their flexible dielectric and magnetic features. They could be used as electronic devices in biological applications. [ABSTRACT FROM AUTHOR]

To control the swelling of sodium carboxymethylcellulose (CMCNa) membranes, mixtures of CMCNa and glutaraldehyde (GA) and mixtures of CMCNa as an organic component and tetraethoxysilane (TEOS) as an inorganic component were prepared, and CMCNa/GA cross-linked membranes and CMCNa/TEOS hybrid membranes were formed. In the separation of an ethanol/water azeotrope by pervaporation (PV), the effects of the GA or TEOS content on the water/ethanol selectivity and permeability of these CMCNa/GA cross-linked and CMCNa/TEOS hybrid membranes were investigated. Cross-linked and hybrid membranes containing up to 10 wt% GA or 10 wt% TEOS exhibited higher water/ethanol selectivity than CMCNa membrane without any cross-linker. This resulted from both increased density and depressed swelling of the membranes by the formation of a cross-linked structure. The relationship between the structure of the CMCNa/GA cross-linked membranes and CMCNa/TEOS hybrid membranes and their permeation and separation characteristics for an ethanol/water azeotrope during PV is discussed in detail. [ABSTRACT FROM AUTHOR]