Hybrid encapsulation structures based on ß-carotene-loaded nanoliposomes within electrospun fibers.

Hybrid encapsulation structures based on ß-carotene-loaded nanoliposomes incorporated within the polymeric ultrathin fibers produced through electrospinning were developed to improve the photostability of the antioxidant. These novel materials were intended to incorporate ß-carotene into water-based food formulations, overcoming the existing limitations associated with its hydrophobic character. Initially, both empty and antioxidant-loaded nanoliposomes were developed and incorporated into polyvinyl alcohol (PVOH) and polyethylene oxide (PEO) solutions. The changes in the solution properties were evaluated to determine their effects on the electrospinning processing. The mixed polymer solutions were subsequently electrospun to produce hybrid nanoliposome-loaded ultrathin fibers. FTIR analysis confirmed the presence of phospholipid molecules inside the electrospun fibers. These ultrathin fibers were evaluated regarding their morphology, diameter, internal ß-carotene distribution and stability against UV irradiation. Liposomal release studies from the electrospun fibers were also undertaken, confirming the presence of the liposomal structures after dissolving the electrospun fibers in water.

Adsorption of antiphospholipid antibodies on affinity magnetoliposomes.

Phosphatidylcholine-based magnetoliposomes containing specific ligands for biological molecules, so-called affinity magnetoliposomes (AML), may prove to be useful as adsorbents in applications such as diagnosis or anchoring and delivery of drugs at specific sites in the human body. In the present study, the performance of affinity magnetoliposomes to adsorb anticardiolipin antibodies (aCL) from a previously characterized pool of patients with autoimmune diseases is described. The magnetic vesicles were prepared by enrobing nanometer-sized colloidal magnetite particles with a phospholipid bilayer composed of dimyristoylphosphatidylcholine (DMPC) and the affinity lipid ligand cardiolipin (CL). Adsorption of antibodies onto the affinity magnetoliposomes assayed using a high-gradient magnetophoresis (HGM) system, in which the magnetoliposomes were first magnetically captured on stainless steel fibers, and which were subsequently overflowed either with a pool of sera from autoimmune patients or sera of healthy individuals as a control. The spectrophotometric assay showed stronger changes in absorbance spectra when the affinity magnetoliposomes containing cardiolipin were added to sera of autoimmune patients than when they were added to sera of healthy individuals. The breakthrough curves obtained from a frontal analyses of the adsorption in the magnetophoresis system showed a 10% difference for total adsorbed IgG when sera of autoimmune and healthy individuals were assayed on magnetoliposomes containing cardiolipin.

Feasibility of treating swine manure in an anaerobic sequencing batch biofilm reactor with mechanical stirring.

Anaerobic sequencing batch reactors containing granular or flocculent biomass have been employed successfully in the treatment of piggery wastewater. However, the studies in which these reactors were employed did not focus specifically on accelerating the hydrolysis step, even though the degradation of this chemical oxygen demand (COD) fraction is likely to be the limiting step in many investigations of this type of wastewater. The mechanically stirred anaerobic sequencing batch biofilm reactor offers an alternative for hastening the hydrolysis step, because mechanical agitation can help to speed up the reduction of particle sizes in the fraction of particulate organic matter. In the present study, a 4.5-L reactor was operated at 30 degrees C, with biomass immobilized on cubic polyurethane foam matrices (1 cm of side) and mechanical stirring provided by three flat-blade turbines (6 cm) at agitation rates varying from 0 to 500 rpm. The reactor was operated to treat diluted swine waste, and mechanical stirring efficiently improved degradation of the suspended COD. The operational data indicate that the reactor remained stable during the testing period. After 2 h of operation at 500 rpm, the suspended COD decreased by about 65% (from 1500 to 380 mg/L). Apparent kinetic constants were also calculated by modified first-order expressions.