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The neotype of amphiphilic oligopeptide (C16 H31 O-AAAGGGGDDIKVAV) was synthesized. The framework of three-dimensional and porous hydrogel self-assembly from the amphiphilic oligopeptide on different conditions was explored. The peptide, whose molecular weight (MW) and purity were detected by Mass Spectrometer (MS) and High Performance Liquid Chromatograph (HPLC) respectively, was synthesized in solid phase methods. Peptide was dissolved in 0.1 mol/L Sodium Hydroxide (NaOH) solution. 200 microl of 10, 2, 1, 0.5 wt% peptide solutions, which were prepared respectively, were added into the same volume of DMEM/F12, or placed into the vapor of 10 mol/L Hydrochloric acid (HCl), or were used to coat in the surface of coverslip and set into the baking oven at 37 degrees C. The self-assembly hydrogel was examined with transmission electron microscope (TEM) and scanning electron microscope (SEM). MS showed that peptide MW was 1438.31. HPLC testified that the peptide purity was 96%. The peptide solution was self-supported into hydrogel triggered with DMEM/F12 in few seconds, or the thin hydrogel after two hours in the vapor of 10 mol/L HCl, or not hydrogel in the baking oven at 37 degrees C. SEM showed that the hydrogel self-assembly from 10 wt% peptide solution was composed of nanofibers that ranked in layers where there were thick voids. TEM showed that the hydrogel self-assembly from 2, 1, 0.5 wt% peptide solution comprised woven network nanofibers, that the nanofibers of hydrogel self-supported from 1 wt% peptide solution varied from 3 to 6 nm in diameter and 100 nm to 1.5 um in length, that the nanofibers of hydrogel self-supported from 2 wt% peptide solution ranked closely, and there were big voids within the thin nanofibers of hydrogel self-supported from 0.5 wt% peptide solution. The amphiphilic oligopeptide was synthesized and self-organized successfully into porous hydrogel characterized as "intelligent" tissue engineering scaffolds containing the bioactive ligand, which was triggered by DMEM/F12.

Sugar-containing monomer vinylbenzylglycosylallyamide (VBG) was synthesized by vinylbenzyl amine and delta-gluconolactone in dimethylformamide(DMF) solution. The sugar-based hydrogel was prepared by free radical crosslinking copolymerization of VBG, itaconic acid (IA) and acrylamide (AM). The release properties of Aspirin from xerogels matrices and from hydrogel in different pH solutions and different concentration NaCl solutions were studied respectively. The release mechanism of Aspirin was further confirmed by evaluating the n value in Peppas equation. The results indicated that the drug release increased with the increase of pH values and with the decrease of NaCl concentration.

Objective: To develop and characterize the hydrogel microspheres for embolization., Methods: N-[tris (hydroxymethyl) methyl] acrylamide-gelatin microspheres (TGMs) were prepared by an inverse suspension polymerization approach. Effects of materials on size, water absorption rate and elasticity of the microspheres were investigated. The materials which were included consisted of gelatin in the range of 10.0-100.0 g/L, N-[tris (hydroxymethyl)methyl]acrylamide in the range of 33.3-200 g/L, cross-linking agent N,N'-methylene-bis-acrylamide in the range of 3.3-10.0 g/L, surfactant Span 80 in the range of 0.5-1.8 g/L, and initiator ammonium persulfate in the range of 1.0-5.0 g/L. The appearance of TGMs was observed under microscope. TGMs were analyzed by infrared spectrum (IR)., Results: The TGMs were round with smooth surface in view of photograph of microscope. The average diameter of TGMs was increased with the increase of gelatin, monomer or cross-linking agent concentrations but decreased with the increase of surfactant or initiator Concentration. The water adsorption rate of the microspheres was decreased with the increase of gelatin or cross-linking agent concentration but not affected by surfactant concentration. The elasticity of TGMs was increased with the increase of monomer or cross-linking agent concentration, decreased with the increase of gelatin concentration, but not affected by surfactant or initiator concentration. All factors above considered, the final prepared TGMs consisted of 10 g/L gelatin, 100.0 g/L monomer, 6.7 g/L cross-linking agent, 0.9 g/L surfactant, and 3.0 g/L initiator. The average diameter of TGMs obtained was about 700.0 microm. The water adsorption rate and the elasticity in accordance with the maximum diameter of the microspheres passed through a microcatheter of TGMs were 12.4 (g/g), and 1 600.0 microm, respectively. The results of IR spectra confirmed the polymerization of monomer, resulting in Nj[tris(hydroxymethyl)methyl]acrylamidegelatin microspheres., Conclusion: The developed TGMs seemed to be suitable for clinical embolization according to the surface, average diameter, elastic and hydrophilic property of TGMs.

In this study, using ethylene carbonate and ethanolamine, we synthesized a novel diol chain-extender, bis-hydroxylethyl carbomate (EC-AE), which contains carbomate structure. The polyurethanes, PUA25 and PUB25, with different extenders, EC-AE and BDO, were synthesized by one-step polymerization, respectively. Their structures were characterized by using FT-IR and DSC. The results indicated that the microphase separation degree of PUA25 was less than that of PUB25, in other words, the amount of hydrogen bonding between hard segments and soft segments in PUA25 was superior to that in PUB25. And the formation of physically crosslinked hydrogels prepared by PUA25 and PUB25 were studied in detail. It was found that only PUA25 can form hydrogel in situ from solution state by cooling. And this kind of hydrogels showed the transition cycle of "gel-sol-gel" under "cooling-heating-cooling" thermal cycles, respectively. The results suggested that the physically crosslinked polyurethane hydrogels were easily possessed in high degree of phase mixing.

Poly(vinyl alcohol) (PVA) hydrogel is a kind of material which has excellent biocompatibility and mechanical properties. In this paper, the researches and developments of PVA hydrogel preparation and the modifications of PVA with other material were introduced. The potential for the use of PVA hydrogels as implant materials in cartilage reparation was reviewed.