The saccharides on the cell surfaces have the bio-signals in the life phenomena, and the biomaterials with molecular recognition abilities were fabricated based on the saccharide. The bio-materials with large molecular recognition abilities were fabricated by the saccharide assembly, which amplified the molecular recognition abilities by the multivalency. The glyco-conjugates with thin layer, nanoparticles and polymers were designed. The glyco-conjugates had the optical and electrochemical functionalities, which were used for the biosensing of proteins and pathogens. We have prepared the glyco-thin layer, which could detect Shiga toxins and amyloid beta peptides. We also prepared the glyco-substrates and glyco-nanoparticles via RAFT living radical polymerization, which showed the high specificity to proteins. Moreover, the glyco-dendrimer with dendrimer showed that the glyco-conjugate could control the protein amyloidosis and cytotoxicity.

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The surface properties of biomaterials, including chemical composition, nano- or microstructured morphology, wettability, elasticity and electrostatic property, are very important for manipulation of stem cell functions such as adhesion, proliferation and differentiation. Photoreactive polyallylamine, poly （acrylic acid）, poly （ethylene glycol） and poly （vinyl alcohol） were grafted or micro-patterned onto cell culture polystyrene plates by UV irradiation. Human mesenchymal stem cells （MSC）, a promising cell source for regenerative medicine were cultured on the polymer-grafted or micropatterned plates to investigate the effect of functional groups on their chondrogenic, osteogenic, and adipogenic differentiation. The adhesion, proliferation, and differentiation of MSC could be manipulated by the polymer-grafted or micropatterned surfaces.

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We prepared rifampicin （RFP）/poly （lactic-co-glycolic acid） （PLGA） nanoparticle-containing mannitol （MAN） microspheres for inhalation therapy of tuberculosis using a four-fluid nozzle spray drier in one step. The uptake of RFP by alveolar macrophages in the lungs of rats from the RFP/PLGA microspheres was very small. The uptake of RFP from the RFP/PLGA nanoparticles, however, was larger because the nano-sized PLGA particles could be retained in the deeper part of the lungs. This study shows that it is feasible to prepare RFP/PLGA nanoparticle-containing microspheres using a four-fluid nozzle spray drier in one step, and that the particles are retained in the lungs for prolonged periods and targeted to alveolar macrophages.

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Application fields of nanoparticles range from biomedicine such as imaging and drug delivery systems to various industrial products. Despite the rapid progress, the potential for nanotoxicity in human has not yet been established. Most methods for toxicity assessment were designed and standardized with chemical toxicology. The reliable toxicity test systems are needed. Here, we present an overview of current in vitro toxicity tests for nanoparticles risk assessment, and focus on genotoxicity, especially cell-specific genotoxicity and its application.

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A new synthesis route to hydroxyapatite microsphere was proposed. Starting from the W/O emulsion system, micron-sized precursor particles were formed autonomously. It was clarified that pH of water during hydrothermal treatment can affect the morphology of resultant hydroxyapatite particles. Particles of irregular shape could be obtained via hydrothermal treatment under ambient pH, by contrast under high-pH conditions resultant particles retain the spherical morphology of precursor particles. It was also clarified that obtained hydroxyapatite particles have negatively charged surface, which is opposite to those by general synthesis method such as precipitation. Eventually it was confirmed that lysozym which is positively charged protein can be adsorbed on the obtained hydroxyapatite particle but albumin which is negatively charged can never be adsorbed.

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Room temperature bioreduction of gold ions was attained within relatively short reaction time (3-120 min) using a metal ion-reducing bacterium Shewanella oneidensis. The soluble gold ions were reduced to gold nanoparticles when formate was provided as an electron donor. The biogenic precipitates in the S. oneidensis cells were gold nanocrystals of approximately 10 nm in size and homogeneously deposited on the bacteria surface. Both the generated particle amount per unit bacterial cell and particles diameters were varied by initial formate concentration and reaction time. In this experiment, the highly dispersed gold nanoparticles could be controlled from 3.8 to 14.2 nm precipitating on the bacteria surface.

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Many formulation technologies have been developed to overcome low-solubility problem of drug candidates. Herein introduced is the application of the electrospray technology as a new option. This method can produce solid amorphous nanoparticles in one-step. Moreover, it can be operated under ambient condition. In the first part of this paper, effect of solution and operation parameters on the particle formation was extensively investigated using chitosan / acetic acid aqueous solutions. Solution viscosity and conductivity were the most important parameters to affect particle size and even the availability of the formulation. The scaled-up study was performed using 8-nozzle manifold, by which prednisolone formulation was prepared with poly (vinyl pyrrolidone) K90. Although the solution of low concentration was preferred to obtain small particles, that of high concentration was favored for effective amorphization. The coaxial nozzle was used to control the surface characteristic of the particle. Dissolution rate of griseofulvin was significantly enhanced by coating the surface by Eudragit L-100.

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We prepared surface-modified poly (DL-lactide-co-glycolide) (PLGA) nanospheres (NS) by an emulsion solvent diffusion method for intracellular drug delivery system. PLGA NS were modified using chitosan (CS) and polysorbate 80 (P80) as a surface modifier to improve their cellular uptake. Polyvinyl alcohol (PVA) is commonly used as emulsifier and dispersion stabilizer in the formulation of PLGA NS. The objective of this study was to determine the factors that influence the amount of adsorbed PVA and surface modifier associated with PLGA NS and its effect on the physical properties and cellular uptake of NS. Adsorbed polymer (PVA, CS and P80) with PLGA NS and physicochemical properties such as zeta potential and surface hydrophobicity were examined. The amount of adsorbed PVA and surface modifiers that remains associated with PLGA NS can be controlled by altering the concentration in the external phase. NS cellular uptake with J774.1 cells was increased by CS or P80 surface modification. Surface property is an important formulation parameter for the cellular uptake of PLGA NS.

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