Narrow Results

In this work we have studied the surface plasmon resonance (SPR) absorption of Albumin on NiSi nanoparticle thin film deposited on Si. The thin films were deposited by means of RF sputtering on Si at various temperatures and times for different thicknesses, and characterized by grazing angle XRD and SEM. From these experimental conditions, we only observed a formation of NiSi nanoparticles deposited on Si at 230°C for 15 min to 30 min. The silicon atoms seem to emerge out of the surface and react with Nickel's. Due to the high activation energy, this mechanism would not take place at lower temperatures, such as RT and 122°C.

Mixture of Albumin and water with varied concentrations has been prepared for the measurement of SPR absorption on the NiSi nanoparticle thin film. We found the spectra of SPR absorption of Albumin on the sample, which NiSi nanoparticle thin film was deposited on Si at 230°C, exhibits a specific shift due to the formation of NiSi nanoparticle.

The endoscopy is a common diagnosis method for the detection of colorectal cancer and there are two methods to improve the diagnostic sensitivity. One is chromoendoscopy, and the other is magnifying endoscopy. Color contrast dye, such as indigo carmine, usually is sprayed on the surface of the intestine and can accumulate in the pits and crevices of the mucosa to enhance the identification of the lesion. However, this color contrast dye does not have target-specific and local-retention properties. For these reasons we encapsulated indigo carmine into chitosan nanoparticles (CNIC) by the ionic gelation to increase the retention time on intestine surface, and conjugated folic acid with chitosan nanoparticles (fCNIC) to target specifically adenomatous polyps. The size and zeta potential of CNIC and fCNIC measured by transmission electron microscope and zetasizer were both at the range of 120–140 nm and 20 mV respectively. The loading efficiency of indigo carmine in fCNIC was in the range of 60–70% and depended on the concentration of acetic acid solution used to dissolve chitosan and folic acid–chitosan conjugates and folic acid conjugation percentage. Bioassy results of fCNIC targeting to HT-29 colon cancer cells revealed that the prepared particle with high folic acid conjugation had a better adhesion effect. These results implied that fCNIC with high folic acid conjugation could serve as an ideal vector for a colon-specific targeting system. According to this concept, we designed a novel detection system to enhance the accuracy of endoscopic diagnosis for colorectal cancer.

A major aim of gene therapy is the efficient and specific delivery of therapeutic gene into the desired target tissues. Development of reliable vectors is a major challenge in gene therapy. The aim of this study is to develop calcium phosphate nanoparticles as novel non-viral vectors for the gene delivery system. Calcium phosphate nanoparticles were prepared by water-in-oil microemulsion method with a water to surfactant molar ratio, Wo $=$ 2–10.

This paper studies the design and synthesis of ultra-low size, highly monodispersed DNA doped calcium phosphate nanoparticles of size around 100nm in diameter. The structure of DNA-calcium phosphate nanocomplex observed by TEM was displayed as a shell-like structure. This study used pEGFP as a reporter gene. The encapsulating efficiency to encapsulate DNA inside the nanoparticles was greater than 80%. In the MTT test, both calcium phosphate nanoparticles and DNA-calcium phosphate nanocomplex have no negative effect for 293T cells. By gel electrophoresis of free and entrapped pEGFP DNA, the DNA encapsulated inside the nanoparticles was protected from the external DNaseI environment. In vitro transfection studies in 293T cell-line, the DNA-calcium phosphate nanocomplex could be used safely to transfer the encapsulated DNA into the 293T cells and expression green fluorescent protein. The characteristic of DNA-calcium phosphate nanocomplex to deliver DNA belongs to slow release. The property of DNA-calcium phosphate nanocomplex was fit in the requirement of non-viral vectors for the gene delivery system.