IMPLANTABLE SELF-REGULATING OSMOTIC INSULIN PUMP

理想的植入式人工胰腺将把胰岛素输送到 糖尿病患者的血糖水平。 这将提供闭环控制， 模拟正常非糖尿病胰腺的内分泌作用。 这样的设计可以防止许多长期并发症 糖尿病，如动脉粥样硬化、肾病和失明。 我们 建议测试自我调节渗透胰岛素的可行性 胰岛素泵，其胰岛素释放速率取决于血糖 浓度. 胰岛素输出的调节是由 新型膜，其对水的渗透性是葡萄糖， 依赖。 这种膜的合成是主要的 提案的重点。 膜将由两个薄层组成。 第一层将葡萄糖转化为葡萄糖酸， 薄层是在葡萄糖酸存在下溶胀的聚合物， 增加其透水性。 我们将确定聚合物 渗透性快速变化所必需的性质 考虑到pH值和最终葡萄糖浓度的变化。 一旦 在优化了膜之后，我们将把它包括在一个原型中， 渗透泵 我们将在体外测试泵，以确定 自我调节渗透泵是否是一种可行的方法， 控制性 我们认为，这一做法将使 与设备相关的某些设计问题，由 其他研究人员，这取决于膜，其渗透性 胰岛素的浓度受血糖水平的调节。

An ideal implantable artificial pancreas would deliver insulin to a diabetic patient in response to the patient's blood glucose level. This would provide closed-loop control of glycemia, and would mimic the endocrine action of the normal, nondiabetic pancreas. Such a devise might prevent many of the long term complications of diabetes, e.g. atherosclerosis, nephropathy and blindness. We propose to test the feasibility of a self-regulating osmotic insulin pump, whose rate of insulin release depends on blood glucose concentration. The regulation of insulin output is determined by a novel membrane whose permeability to water is glucose- dependent. The synthesis of such a membrane is the primary focus of the proposal. The membrane will consist of two lamina. The first lamina converts glucose to gluconic acid, and the second lamina is a polymer that swells in the presence of gluconic acid, increasing its water permeability. We will determine the polymer properties that are necessary for rapid changes in permeability given changes in pH, and ultimately glucose concentration. Once having optimized the membrane, we will include it in a prototype osmotic pump. We will test the pump in vitro to determine whether self-regulated osmotic pumping is a feasible means of controlling glycemia. We believe that this approach will obviate certain design problems associated with devices, proposed by other researchers, that depend on membranes whose permeability to insulin is modulated by blood glucose levels.