A Miniaturized Nafion-Based Glucose Sensor: in vitro and in vivo evaluation in dogs:

摘要: We have developed an implantable glucose sensor based on a new tri-layer membrane configuration. The needle-type integrates Pt working electrode and Ag/AgCl reference electrode. Its size is equivalent to 25 gauge needle (0.5 mm in diamater). Poly (o-phenylenediamine) was used as inner coating reduce interference by small compounds present the body fluids, perfluorinated ionomer, Nafion biocompatible, protective, outer coating. Glucose oxidase trapped albumin/glutaraldehyde matrix sandwiched between these coatings. In vitro tests buffer showed sensors had good selectively, sensitivity of about nA/mM, 90% response time 33 s. Stabilization current following polarization required 10 30 min 40 vivo. Although remained stable for many weeks saline solution, their implantation animals resulted degradation protective coating, which turn, led failure incorporated demonstrated that if unprotected, AgCl layer rapidly dissolves biological environment. However, we later vivo can be prevented heat curing. When cured were subcutaneously implanted dogs, sensors' signal closely followed plasma level during tolerance tests. dogs retained days.