Abstract: This invention relates to a sensor suitable for detecting the presence of one or more analytes. The sensor comprises a substrate; a confinement structure disposed on the substrate, wherein the confinement structure comprises at least a first limiting structure defining a first interior space; a transducer proximal to the first interior space; and a first synthetic polymer capable of selectively binding a first analyte, within the confinement structure. The confinement structure may have a second or further limiting structure defining a second or further interior space containing the first or preceding interior space. The sensor may also have additional confinement structures containing different materials for detecting additional analytes or taking reference measurements.

Abstract: A method of positioning a sensor in a human or animal body tissue comprising the steps of: i. providing a flexible stylet capable of penetrating the tissue, ii. providing flexible tubing having a bore capable of receiving separately the stylet and the probe; iii. positioning the stylet received in the tubing in the tissue; iv. removing the stylet; v. inserting the probe in the bore of the tubing; and vi. removing the tubing.