The Subcutaneous Ultrafilter Infusion Device (SQUID) is a semi- permanent transcutaneous device with 30,000 m.w. cutoff membranes which lie under the skin and distribute drugs to the subcutaneous tissue. The Capillary Filtrate Collector (CFC) is a similar collection of membranes which, under vacuum, creates an ultrafiltrate with the same concentration of glucose as plasma. In preliminary studies, we used a tape-based system to measure glucose measurement on CFC fluid, a roller pump to infuse insulin to the SQUID and created a continuous feedback- controlled insulin infusion system (FII system), which was then tested in rats with streptozotocin-induced diabetes. In Phase I of this project, we will physically combined the CFC and SQUID devices to include a single transcutaneous tube and amplify the insulin infusion components (using the Minimed 507 pump). We will then further test the system for control of blood glucose in diabetic rats. In Phase II we will simplify the glucose measurement system by use of a glucose oxidase electrode to measure glucose levels in the CFC filtrate, and implement an FII system using this measurement. This system will allow development of an FII system which is small, integral and potentially wearable. PROPOSED COMMERCIAL APPLICATIONS: Insulin pumps have grown in use for diabetic patients who desire close control of glucose levels, now over 50,000 patients in the U.S. Most of these patients would choose a semi-permanent SQUID device for insulin infusion if it were proven safe and effective for one month of use or more, rather than placing new needles or catheters each few days. Many more would wear a feedback-controlled insulin infusion system with a similarly durable access device, if proven safe and effective. The SQUID device also has potential for treatment of many other medical conditions where continuous drug therapy is necessary including cancer, hepatitis, chronic pain and hormonal deficiencies.
