Method for the preparation of a working electrode

A method of preparing a working electrode on a sensor substrate, comprising:

• a) providing a sensor substrate having a first side with at least one conductive trace;
• b) applying a layer of sensing material having an un-crosslinked polymeric material onto the first side, wherein the sensing material covers at least a portion of the at least one conductive trace;
• and
• c) irradiating the layer of the sensing material with a laser beam, wherein at least a first portion of the layer of the sensing material is at least partially removed and wherein at least a second portion of the sensing material covering the at least one conductive trace is preserved on the first side of the sensor substrate to obtain a working electrode on the sensor substrate;
• d) applying a membrane layer that at least partially covers the working electrode, wherein the membrane layer comprises a cross-linker configured for cross-linking to the un-crosslinked polymeric material of the sensing material;
• and
• e) a diffusion step in which the cross-linker in the membrane layer at least partially diffuses into the sensing material.