Use of Alginate to Reduce Hematocrit Bias in Biosensors
Methods and devices for determining the concentration of a constituent in a body sample are provided. The body sample is introduced into a biosensor having a sample chamber and at least part of an electrode disposed therein. The biosensor also includes an alginate hydrogel substantially covering a portion of the sample chamber. The alginate hydrogel substantially includes an alginate polymer configured to reduce cellular migration.
1 . A biosensor, comprising:
a sample chamber;
an electrode, wherein at least part of the electrode is located in the sample chamber; and
an alginate hydrogel substantially covering a portion of the sample chamber, wherein the alginate hydrogel substantially comprises an alginate polymer.
2 . The biosensor of claim 1 , wherein the alginate hydrogel covers at least part of the electrode.
3 . The biosensor of claim 1 , wherein the alginate hydrogel is at least partially cross-linked.
4 . The biosensor of claim 3 , wherein the alginate hydrogel includes a divalent ion.
5 . The biosensor of claim 4 , wherein the divalent ion includes at least one of a barium ion, a calcium ion, and a strontium ion.
6 . The biosensor of claim 3 , wherein the alginate hydrogel includes an average pore size ranging from about 1 micron to about 10 microns.
7 . The biosensor of claim 1 , wherein the biosensor includes at least one of a mediator, and an oxidoreductase.
8 . The biosensor of claim 7 , wherein the mediator includes potassium ferricyanide.
9 . The biosensor of claim 7 , wherein the oxidoreductase includes at least one of glucose dehydrogenase, and glucose oxidase.
10 . An analyte testing system, comprising:
a meter system for making a measurement of an analyte concentration in a body sample, wherein the meter system is configured to use the biosensor of claim 1 .
11 . A method of manufacturing a biosensor, comprising:
forming at least part of a sample chamber;
forming an electrode, wherein at least part of the electrode is located in the sample chamber; and
applying an alginate hydrogel to at least partially cover a portion of the sample chamber, wherein the hydrogel substantially comprises an alginate polymer.
12 . The method of claim 11 , wherein the alginate hydrogel covers at least part of the electrode.
13 . The method of claim 11 , further comprising the step of at least partially cross-linking the alginate hydrogel.
14 . The method of claim 13 , wherein the step of cross-linking further comprises providing a divalent ion.
15 . The method of claim 14 , wherein the divalent ion includes at least one of a barium ion, a calcium ion, and a strontium ion.
16 . The method of claim 11 , further comprising the step of applying to the sample chamber at least one of a mediator, and an oxidoreductase.
17 . The method of claim 16 , wherein the step of applying the mediator further comprises applying potassium ferricyanide.
18 . The method of claim 16 , wherein the step of applying the oxidoreductase further comprises applying at least one of glucose dehydrogenase, and glucose oxidase.
19 . The method of claim 11 , wherein the step of applying the alginate hydrogel comprises a process selected from the group consisting of screen-printing, spray deposition, piezo printing, pipetting, and ink jet printing.
20 . A reel for manufacturing biosensors, comprising:
a generally planar base layer including a plurality of at least partially formed sample chambers located thereon, wherein at least part of an electrode is located in each sample chamber; and
an alginate hydrogel at least partially covering a portion of each sample chamber, wherein the alginate hydrogel substantially comprises an alginate polymer.
21 . The reel of claim 20 , further including a plurality of registration points formed on the generally planar base layer.
22 . The reel of claim 21 , wherein the plurality of registration points are formed by a process selected from the group consisting of laser ablation, etching, drilling, printing, punching, scoring, heating, compression and molding.
23 . The reel of claim 20 , wherein the alginate hydrogel covers at least part of the electrode.
24 . The reel of claim 20 , wherein the alginate hydrogel is at least partially cross-linked.
25 . The reel of claim 24 , wherein the alginate hydrogel includes a divalent ion.
26 . The reel of claim 25 , wherein the divalent ion includes at least one of a barium ion, a calcium ion, and a strontium ion.
27 . The reel of claim 24 , wherein the alginate hydrogel includes an average pore size ranging from about 1 micron to about 10 microns.
28 . The reel of claim 20 , wherein each sample chamber includes at least one of a mediator, and an oxidoreductase.
29 . The reel of claim 28 , wherein the mediator includes potassium ferricyanide.
30 . The reel of claim 28 , wherein the oxidoreductase includes at least one of glucose dehydrogenase, and glucose oxidase.