Abstract: There is presented an electrochemical sensor (100) for sensing an analyte in an associated volume (106), the sensor comprising a first solid element and a second solid element being joined to the first solid element, a chamber (110) being placed at least partially between the first solid element and the second solid element, said chamber comprising a reaction region (130), and a reservoir region (132) being connected with the reaction region, wherein an one or more analyte permeable openings (122) connect the reaction region (130) with the associated volume (106), and wherein the electrochemical sensor (100) further comprises an analyte permeable membrane (124) in said one or more analyte permeable openings, a working electrode (104) a reference electrode (108), and a guard electrode (109) arranged so as to enable reduction or oxidation of at least some reactants from at least a part of the reservoir region.

Abstract: A electrochemical sensor (100) for sensing an analyte in an associated volume (106), the sensor comprising a first solid element (126), a second solid element (128) being joined to the first solid element, a chamber (110) being placed at least partially between the first solid element and the second solid element, a working electrode (104) in the chamber (110) and wherein one or more analyte permeable openings (122) connect the chamber with the associated volume (106) and wherein the electrochemical sensor (100) further comprises an analyte permeable membrane (124) in said one or more analyte permeable openings, and wherein the one or more analyte permeable openings are arranged so that a distance from any point in at least one cross-sectional plane to the nearest point of a wall of said opening is 25 micrometer or less.

Abstract: There is presented an electrochemical sensor (100) for sensing an analyte in an associated volume (106), the sensor comprising a first solid element (126), a second solid element (128) being joined to the first solid element, a chamber (110) being placed at least partially between the first solid element and the second solid element, a working electrode (104) in the chamber (110), a reference electrode (108), and wherein one or more analyte permeable openings (122) connect the chamber (110) with the associated volume (106), and wherein the electrochemical sensor (100) further comprises an analyte permeable membrane (124) in said one or more analyte permeable openings, wherein the one or more analyte permeable openings are placed at least partially between the first solid element and the second solid element.