Catheter-free implantable needle biosensor
Electrochemical biosensors consisting of two or more needle-shaped electrodes for monitoring of molecules such as glucose in the subcutaneous tissue are provided. The two electrodes are parallel to each other, and are fixed perpendicularly to the planar side of a sensor base which provides skin fixation and electric connection. The needle electrodes are made of rigid conducting materials, capable of inserting into the skin without the need of catheters. One electrode is the sensing electrode and the other, the reference electrode. A compound sensing membrane is attached onto the sensing electrode surface to detect analyzed molecules.
1. A percutaneously implanted miniature sensor assembly, comprising a base, an anode, a reference cathode, an assisting cathode, a first contact plate, a second contact plate and a third contact plate; wherein the base further comprises a first mounting hole surface, a second mounting hole surface, a third mounting hole surface, a base top surface and a base bottom surface, wherein the first mounting hole surface defines a first mounting hole, the second mounting hole surface defines a second mounting hole, and the third mounting hole surface defines a third mounting hole; wherein the first contact plate further comprises a first plate mounting surface defining a first plate mounting hole, the second contact plate further comprises a second plate mounting surface defining a second plate mounting hole, and the third contact plate further comprises a third plate mounting surface defining a third plate mounting hole respectively; wherein the first contact plate, the second contact plate and the third contact plate are set on the base on the base top surface, wherein the first plate mounting hole, the second plate mounting hole, the third plate mounting hole are in line with the first mounting hole, the second mounting hole and the third mounting hole respectively; wherein the anode, the referencing cathode and the assisting cathode are in needle shape and implantable in a body, wherein the upper end of the anode penetrated the first plate mounting hole and the first mounting hole, the upper end of the referencing cathode penetrated the second plate mounting hole and the second mounting hole, and the upper end of the assisting cathode penetrate the third plate mounting hole and the third mounting hole, wherein the top of the anode, the referencing cathode and the assisting cathode are connected with the first contact plate, the second contact plate, and the third contact plate by electric conductive material, wherein the anode, the referencing cathode and the assisting cathode are perpendicular to the base bottom surface respectively.