稳定的无皂阳离子共聚物乳粒性质及乳液性能的研究

选用苯乙烯（Ｓｔ）、丙烯酸丁酯（ＢＡ）和少量的Ｎ，Ｎ—二甲基，Ｎ—丁基，Ｎ—（３—甲基丙烯酰胺基）丙基溴化铵（ＤＢＭＰＡ），以阳离子自由基型引发剂进行无皂乳液聚合，合成了稳定的无皂阳离子共聚物乳液，用粒度分布仪表征了胶平均直径、数目，用离子交换—电导滴定分析胶粒表面性质；通过表面张力、ＤＳＣ等分析了胶乳的稳定性和胶膜的结构性能。

Study on Properties of Composite Oxides TiO_2/SiO_2

The nanometer particles of TiO_2 and TiO_2/SiO_2 oxides wereprepared by sol-gel supercritical fluid drying method. The propertiesof TiO_2 and TiO_2/SiO_2 were characterized by means of BET(Brunner-Emmett- Teller method), TEM (transmission electronmicroscopy), SEM (scanning electron microscopy), XRD (X-ray diffrac-tion) and FTIR (Fourier transform-infrared) techniques. The effectsof different preparation route, prehydrolysis and non-prehydrolysis,on the properties of TiO_2/SiO_2 oxide were also examined.

Multi-methodological Approach to Evaluate Performances of Mucoadhesive Oral Gel Based on Nanoparticles

Oral mucositis due to chemotherapy and irradiation continues to be an important clinical problem. The effectiveness of hyaluronic acid-based compounds in accelerated healing and helping manage pain in patients with oral mucositis was demonstrated. It was investigated a protective and regenerative effect of hyaluronic acid based gel formulation enriched with NAG （N-acetyl glucosamine） loaded solid lipid nanoparticles against degenerative process of the oral mucosa. Gel formulations were obtained by adding sHA （sodium hyaluronate） into SLN aqueous suspension. Gel performances were evaluated by multi-methodological approach： mucoadhesive and barrier properties evaluation, cell viability. It was shown that gel formulation based sHA, enriched with NAG loaded SLNs, when added as suspension, demonstrated to have a good mucoadhesion profile comparable in terms of tensile work and fracture strength to Carbomer 934 2%. The presence of NAG encapsulated and not in gel formulation enhances also the biocompatibility of the system, demonstrating also to have a proliferative effect. Finally, any barrier property was altered. Finally, results demonstrated that sHA based gel formulation enriched SLNs, demonstrated good mucoadeshion property, comparable to carbopol gel, positive control. The proposed gel formulation enriched with SLNs setting up in this work could be used as innovation strategy to treat oral mucositis.

Stabilization of Magnetite Nanoparticles by Encapsulation into the Silica Matrix

Different methods have been investigated for the synthesis of magnetic nanoparticles. Control of the particle size, dispersion, purity and stability have been always regarded an issue. In this study magnetite （Fe304） superparamagnetic nanoparticles with a size range about 20 nm have been successfully synthesized using chemical co-precipitation method from the solution of ferrous/ferric mixed salt-solution in alkaline media in oxygen-free environment. The sol-gel method has been chose to encapsulate magnetic nanoparticles into silica matrix. The phase structures, morphologies, surface area, functional classes and magnetic properties have been characterized by X-ray diffraction, SEM and AFM, BET, FT-IR and VSM. The results showed that the resultant films, consisting of encapsulated magnetite have crack free and smooth surface with a roughness value 1.5 rim.

Sol-Gel Synthesis and Structure-Property Relations in Nd4-xCs2（1＋x）Fe5-xZnxO14＋δ（0≤x≤1.0） Oxide Systems

Synthesis of composite oxides in the series Nd4-xCs2（1＋x）Fe5-xZnxO14＋δ（0≤x≤1.0） （B1-B5： x= 0.0, 0.25, 0.5, 0.75, 1.0） is performed by sol-gel method via nitrate-acetate precursor route. Analysis of the powder x-ray diffraction （XRD） patterns show tetragonal unit cell with lattice parameters a = 8.6545, 8.2520, 7.7645, 9.8952, 8.2863 A; b = 8.9800, 11.5788, 15.6305, 8.4766, 11.6465 A in B1-B5, respectively. The average crystallite sizes in the samples are found to be in the range 69.56-119.48 A. Energy dispersive analysis of x-rays （EDAX） result shows the presence of Fe, Nd, Cs and O, and Fe, Nd, Zn, Cs and O in B 1 （x=0） and B2（x=0.25）-B5（x= 1.0）, respectively. The IR results at 300 K show the presence of octahedral [NdO6/2]^3- （asymmetric stretch： 410-416 cml） and [FeO6/2]^3-（symmetric stretch： 562-572 cm^-1） units in the samples. Observed magnetic moments versus magnetic field plots in the range -10 kG to ＋10 kG exhibit hysteresis loops with average magnetic susceptibility values in the range 3.46 × 10^-5 -7.05 × 10^-5 emu/gG in B1-B5 shows fairly strong ferromagnetic nature of the samples. The observed EPR lineshapes at 300 and 77 K with giso=2.01-2.03 and giso=2.01-2.03, respectively is ascribed to the octahedral [FeO6/2]^3- coordination of Fe^3＋ （3d^5） ion. The optical absorption spectra show the transition of ^4I9/2→^4F7/2→^ 4S3/2 （750 nm） of optically active Nd^3＋ ions in samples.

Preparation and characterization of zinc oxide nanoparticles

In the present study, the zinc oxide nanoparticles(ZnO NPs) were prepared by using a sol-gel method. The characterization of ZnO NPs, such as particle size, morphology, crystal form, optical properties and p H-responsive behavior, was carried out. The in vitro anti-tumor activity of ZnO NPs was evaluated on PC-3M and 4T1 cell lines. The results indicated that ZnO NPs were spherical NPs with uniform particle size, excellent fluorescence properties, and p H-responsive behavior. The in vitro anti-tumor activity of ZnO NPs was observed on PC-3M and 4T1 cell lines. Considering to above characteristics, Zn O NPs could be used as drug delivery carries for loading active compound performing therapeutic and diagnostic effect.