Chitosan-Based Nanoparticles as Effective Drug Delivery Systems-A review.

Chitosan-based nanoparticles (chitosan-based nanocomposites; chitosan nanoparticles; ChNPs) are promising materials that are receiving a lot of attention in the last decades. ChNPs have great potential as nanocarriers. They are able to encapsulate drugs as well as active compounds and deliver them to a specific place in the body providing a controlled release. In the article, an overview has been made of the most frequently used preparation methods, and the developed applications in medicine. The presentation of the most important information concerning ChNPs, especially chitosan's properties in drug delivery systems (DDS), as well as the method of NPs production was quoted. Additionally, the specification and classification of the NPs' morphological features determined their application together with the methods of attaching drugs to NPs. The latest scientific reports of the DDS using ChNPs administered orally, through the eye, on the skin and transdermally were taken into account.

The effect of chitosan/TiO2/hyaluronic acid subphase on the behaviour of 1,2-dioleoyl-sn-glycero-3-phosphocholine membrane.

The main aim of the study was to determine the effect of two polysaccharides: chitosan (Ch) and hyaluronic acid (HA), and/or titanium dioxide (TiO2) on the structure and behaviour of the 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) membrane. To achieve this goal the surface pressure as a function of the area per molecule (π-A) isotherm for the phospholipid monolayer was recorded. The shape of the π-A isotherms and compression-decompression cycles, as well as the compression modulus values, were analysed in terms of biocompatibility. Besides, morphology and thickness of the phospholipid layers obtained by means of Brewster angle microscope at different π, were determined. The obtained results show that both polysaccharides Ch, HA, as well inorganic TiO2 affect slightly the structure of the DOPC monolayer but do not disrupt it. Their presence brings no typical arrangements of both the polar heads and tails of DOPC molecules at the interface.

Effect of UV radiation and chitosan coating on the adsorption-photocatalytic activity of TiO2 particles.

The effect of chitosan, pH and UV-VIS radiation on the adsorption-photocatalytic properties of TiO2 dispersion was investigated on the basis of electrophoretic mobility, as well as spectrophotometric and dynamic light scattering measurements. For the degradation efficiency tests two different dyes: the cationic - methylene blue and the anionic - sunset yellow were used. The stability and photodegradation experiments were performed by varying the parameters: wavelength of light (range 450-750 nm), type and radiation time (UV and VIS; 0-5 h), pH (3 and 6) and pigment concentration (0.6 × 10-5-3.6 × 10-5 mol/dm3). In the chitosan-modified dispersions polysaccharide exhibits synergism of adsorption-photocatalytic properties of TiO2. Chitosan increases the biodegradability of the chitosan/TiO2 composite and additionally, it can be potentially used as a promising anti-microbial material.