The Fabrication And Study In Vitro Of Artifical Cell Based On TiO₂/Ti Composite Membrane

The artificial cells were developed by combination of immunoisolation and cell transplantation. It can resolve the two problems of organ transplantation―limited donor source and immunological rejection. At present, the artificial cell is mostly made from gelatinous natural or synthetic polymer material. The defects in such material prevent atificial cells from applying to clinic, such as water swelling, poor mechanical strength, residual toxicity monomer and so on, especially, some virus of transplanted cells maybe invade into human body and result in unexpected effects. In view of this, the artificial cells based on TiO2/Ti composite membrane were firstly presented. The feasibility and preparation conditions were investigated by the experiment of immunoisolation effect. The artificial hypothalamic neurons and artificial islet cells were firstly made from TiO2/Ti composite membranes. The contents and productions of research were summarized as follows.The TiO2/Ti composite membranes with support of porous Ti were prepared by sol-gel method. The prepared condition of the composition membrane in application to artifical cell as follows. When the average pore diameter of porous Ti support was between 1-2μm, the better sintering temperature and coating times of TiO2/Ti composition, which have good effect on immunoisolation, were less than 800℃and exceeded 3 times, respectively. If the average pore diameter of porous Ti support was less than 1μm, the sintering temperature must be controlled at 600-700℃, and the coating times must be less than 3times.The hypothalamic neurons planted in TiO2/Ti composite membrane and cultured in vitro. The results showed that the bioactivity of TiO2/Ti composite membranes was enhanced by increasing the content of rutile TiO2.The artifical hypothalamic neurons based on TiO2/Ti composite membranes were firstly prepared. The encapsulated hypothalamic neurons not only survived and grew, but also could adjust theβ-endorphin secretion by themselves, in order to remain a stable balance ofβ-endorphin level between in intracellular fluid and in extracellular fluid. The secretion of artifical neurons could effectively inhibit the naloxone-precipitated withdrawal contracture in isolated ilea of rates, which were exposed to morphine. From these results, it was presumed that opiate dependence could be cured by artificial hypothalamic neurons transplantation.The artifical islet cells based on TiO2/Ti composite membranes were firstly prepared by transition fit. The kind of artifical islet cells could automatic adjust the release of insulin based on the concentration of glucose in extracelluar fluid. It is a promising treatment of diabetes.Summing up above results, the TiO2/Ti composite membranes, which have good immunoisolation effect, can be prepared by adjusting the condition of preparation, such as sintering temperature, coating times. The artifical cell based on such material have the virtue of undecomposition, good bioactivity and high mechanical strength and can promote the development of artifical cell transplantation, especially in the development of clinic application of xenotransplantation.