Wearable device with improved microneedle array

A wearable biosensor device comprising

• a microneedle array comprising a substrate with microneedles disposed on the substrate, said microneedle array comprising an electrically insulative material, and at least a portion of the microneedle array being coated with an electrically conductive layer, wherein at least some of the microneedles are configured as electrochemical sensor electrodes to detect an electrical signal from a reaction with a target analyte in a biofluid exposed to the microneedle array, wherein at least one of the microneedles is a working electrode functionalized with at least one chemical layer positioned on the electrically conductive layer and configured for producing an electrical signal from a reaction with a target analyte in a biofluid, and the microneedles comprise a base, a body region, and a tip region comprising an off-center tip,
• a cover unit to couple with the substrate, the cover unit comprising a sensor-cover component formed of the electrically insulative material having an array of first openings configured to align with the array of
• microneedle structures on the substrate, such that the off-center tip and at least a distal portion of the body region of the microneedles pass through the array of first openings of the sensor-cover component of the cover unit, wherein a bottom portion of the cover unit and/or the substrate comprise microfluidic channels containing a cured custom resin extending upward to a cut-off fluidic line forming a base structure on a respective microneedle, the cured custom resin insulating and securing the cover unit to the substrate and the microneedles, and
• a plurality of electrical interconnections connecting the electrically conductive layer at a contact terminus in or on the substrate with an electronics unit.