Tissue engineering is an interdisciplinary field that applies the principles of the engineering and the life sciences to the development of biological substitutes which restore, maintain, or improve tissue function. Three general strategies have been adopted for the creation of new tissue: the tissue-inducing substances, cell biology, biomedical nature and the evaluation of safety. This article discussed the new development and tendency of the research in bone, cartilage, skin tissue engineering.

目的 探讨以胶原-硫酸软骨素支架材料构建人工真皮的可行性。方法 以碳化二亚胺（EDC）为交联剂构建胶原-硫酸软骨素（CS）支架体系。通过光电子能谱、扫描电镜、HE染色观察及力学性能测试等对材料的理化性能进行表征。同时分离培养人胚真皮成纤维细胞，将体外扩增的成纤维细胞接种在支架上，制备人工真皮。通过组织学、免疫组织化学，与传统的胶原海绵人工真皮的性质进行比较。结果 胶原-CS支架是三维多孔海绵状结构且空隙均匀，与胶原支架比较，断裂强度提高，并且材料表面极性基团增加。成纤维细胞在胶原-CS支架材料上生长良好，形成人工真皮。结论 胶原-CS人工真皮具有优越的生物学和力学性能，成纤维细胞在胶原-CS支架上黏附、增殖情况优于胶原真皮。

纳米技术是在纳米尺度下对物质进行制备、研究和工业化，以及利用纳米尺度物质进行交叉研究和工业化的综合性研究体系。本文对利用纳米技术发展分子工程，包括纳米生物分子机器人和纳米信息处理系统，研究生物大分子，研究组织工程支架材料，研究药物载体，发展诊断与监测技术，以及纳米技术在生物医学研究领域的发展趋势作了综述，并展望了纳米技术在生物医学领域的发展前景。

Thermal properties of PHB and PHB/PEG blends were investigated by differential scanning calorimetry (DSC) and melt index (MI) test. DSC thermograms indicate that two components of blend are miscible. From the DSC thermogram, we can also conclude that the melting point of PHB descends with the increased content of PEG, this can improve PHB processing properties. From MI data, we may draw the same conclusion.

Naturally derived collagen protein was mixed thoroughly with medical grade poly (vinyl alcohol) (PVA) at the ratio of 90: 10 (w/w) and was crosslinked by formaldehyde to form a homogeneous composite membrane. The bulk structure of the membrane was characterized by means of X-ray diffraction (XRD) and transmission electron microscopy (TEM). The membrane surface structure was investigated using Fourier transform-infrared spectroscopy (attenuated total refraction) (FTIR-ATR), electron spectroscopy for chemical analysis (ESCA) and contact angle measurement. It was found that collagen and PVA can remain stable. This was supported by the fact that no sign of phase separation1 had been observed. The use of crosslinking agent can substantially influence the structure of the composite. It is suggested that this new composite deserves further investigation and is potentially usable as a biomedical material.

Collagen materials were crosslinked by 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC) in the presence of chondroitin sulfate (CS), one of glycosaminoglycans (GAGs). PVA and chitosan were also blended with collagen. The physical and chemical properties of the matrices were characterized by SEM, DSC, and ESCA, L929 cells were implanted on the matrices to show the cytotoxic and the biological characters of the materials, The results indicate that EDC is an effective and non-cytotoxic cross-link reagent, which can replace the common dialdehyde reagent. The attachment of CS can improve the stability of collagen and accelerate cell growth The addition of PVA can prepare porous matrices with smaller bore size. There are reactions between the chitosan and collagen, and the composite has good biological character, The presence of chitosan can also increase the amount of incorporated CS.

In this article, nature derived collagen was mixed with chitosan and crosslinked by formaldehyde to form a homogeneous composite membrane. The microstructure of the composite was characterized by transmission electron microscopy and differential scanning calorimetry. Mechanical and swelling properties of the composite were improved compared with pure collagen and can be modulated via changing the crosslinking conditions, such as pH, time, and concentration.

Lomustine (CCNU) microcapsules was prepared by improved recoacervation method, then mixed mierocapsules with 0.7% collagen swelling solution to prepare the emulsion, spreaded the emulsion on the plate to form membrane and cross-linked it, the membrane would be planted into body and was expected to release at steady speed. The concentration of CCNU and the CCNU content of microcapsoles were measured by ultraviolet spectrophotometry to observe the release of CCNU be slow and constant, approach to O-class release approximately.

In this paper, we review some mafor progrosses made in the field of biomedical materials research on the application of collagen protein and its composites formed with certain synthetic polymers (e. g., polyhydroxvethyl methacrylate and polyvinyl alcohol). Some potential development and application of the materials are discussed tentatively. Due to their biocompatibility and physico-chemical properties, the collagen-synthetic polymer hydrogels will find wide application in soft tissue substitution, drug release system, guided tissue regeneration, and tissue engineering.