Working electrode of a continuous biological sensor

Inventors

Boock, Robert James • Zhang, Huashi

Assignees

Allez Health Inc

Abstract

A working electrode for a subcutaneous sensor for use with a continuous biological monitor for a patient is disclosed. The working electrode includes a conductive substrate and a carbon-enzyme layer on the conductive substrate. The carbon-enzyme layer includes a polyurethane or silicone crosslinked with an acrylic polyol, and an enzyme fully entrapped by the polyurethane or silicone crosslinked with the acrylic polyol. The enzyme is selected according to a biological function to be monitored. The carbon-enzyme layer also includes a carbon material. The carbon-enzyme layer is electrically conductive and facilitates a generation of either peroxide or electrons within the carbon-enzyme layer responsive to reacting the enzyme with a target biologic from blood of the patient.

Core Innovation

The disclosure relates to a continuous biological monitoring sensor architecture and a low-cost, platinum-free working electrode for a subcutaneous sensor used with a continuous biological monitor for a patient. The working electrode includes a conductive substrate and a carbon-enzyme layer on the conductive substrate, where the carbon-enzyme layer is electrically conductive and facilitates a generation of either peroxide or electrons within the carbon-enzyme layer responsive to reacting the enzyme with a target biologic from blood of the patient.

In one implementation, the carbon-enzyme layer includes polyurethane crosslinked with an acrylic polyol, with an enzyme fully entrapped by the polyurethane crosslinked with the acrylic polyol. In another implementation, the carbon-enzyme layer includes silicone crosslinked with an acrylic polyol, with the enzyme fully entrapped by the silicone crosslinked with the acrylic polyol, and the carbon-enzyme layer further includes a carbon material to enable electrical conductivity and peroxide or electron generation.

The disclosure further describes improving sensor behavior by adding a glucose limiting layer over the carbon-enzyme layer to restrict how much glucose from a patient's blood reaches the carbon-enzyme layer, and by using an interference membrane that is non-electron-conducting, ion-passing, and permselective to regulate hydrogen peroxide to the conductor and reduce oxidation/fouling. An aqueous emulsion enzyme layer is also described where the enzyme is evenly distributed and fully entrapped using polyurethane crosslinked or self-crosslinked with an acrylic polyol, and carbon-enzyme layers are described that can directly generate free electrons or peroxide without requiring platinum.

Claims Coverage

The provided claims include two independent claims. Each claim centers on a subcutaneous working electrode with a conductive substrate and a carbon-enzyme layer that uses a crosslinked polymer host to fully entrapped an enzyme and enable electrical conductivity with peroxide or electron generation responsive to a target biologic from blood.

Across both independent claims, the inventive coverage is directed to platinum-free working electrodes that include a conductive substrate and an electrically conductive carbon-enzyme layer in which an enzyme is fully entrapped within either a polyurethane–acrylic polyol network or a silicone–acrylic polyol network, together with a carbon material to facilitate peroxide or electron generation responsive to reacting with a target biologic from blood.

Stated Advantages

Documented Applications