Electrochemical sensors for determination of analyte concentrations in fluids for medical purposes; Medical device and surgical instrument for use in diagnosis and surgery of the gastro-intestinal tract; Medical instruments for use in remote biosensing of gastrointestinal, cardiovascular, pulmonary, and urological diseases; Medical instruments to measure blood pressure, cardiac output and other physiological and cardiovascular parameters; Medical instruments, namely, biosensors for detecting infectious diseases; Medical products, namely, biofeedback sensors; Medical, surgical and orthopaedic implants made of artificial materials; Surgical apparatus and instruments for medical, dental or veterinary use