Biosensor and method of making
View Patent ↗An electrochemical biosensor with electrode elements that possess smooth, high-quality edges. These smooth edges define gaps between electrodes, electrode traces and contact pads. Due to the remarkable edge smoothness achieved with the present invention, the gaps can be quite small, which provides marked advantages in terms of test accuracy, speed and the number of different functionalities that can be packed into a single biosensor. Further, the present invention provides a novel biosensor production method in which entire electrode patterns for the inventive biosensors can be formed all at one, in nanoseconds—without regard to the complexity of the electrode patterns or the amount of conductive material that must be ablated to form them.
1. A biosensor used to measure presence or concentration of an analyte in a fluid sample, said biosensor being produced by:
(a) providing an electrically conductive material on a base;
(b) removing a portion of the electrically conductive material by broad field laser ablation to form an electrode set on the base wherein the biosensor having the electrode set includes at least two co-planar electrodes on the base;
(c) providing a reagent at least partially covering the base; and
(d) adhering one or more layers to the base, the one or more layers cooperating to form a sample-receiving chamber and a cover for the biosensor, at least a portion of both the reagent and the electrode set being positioned in the chamber.
2. The biosensor of claim 1 , wherein the electrode set includes first and second electrode elements having first and second respective edges defining a gap therebetween, the gap having a width and a length; and
the first edge being spaced from a first theoretical line by a first distance that varies along the length of the gap, the first theoretical line defining a desired shape and placement of the first edge, wherein the standard deviation of the first distance is less than about 6 μm over the entire length of the gap.
3. The biosensor of claim 1 , wherein the step of removing a portion of the electrically conductive material comprises removing at least 10% of the electrically conductive material to form at least two electrode sets on the base, the electrode sets having different feature sizes.
4. The biosensor of claim 1 , wherein the electrode set includes at least two electrode patterns having different feature sizes.
5. The biosensor of claim 4 , wherein at least one electrode pattern has at least one edge extending between two points, a standard deviation of the edge from a line extending between two points is less than about 6 μm.