Electrochemical cell sensor for continuous, short-term use in tissues and blood

Claim 2

An electrochemical cell sensor capable of being implanted into an animal body comprising: a housing with an opening or openings in the walls of said housing; when inplanted being electrode means situated in said housing and,/in fluid communication with fluids present in said animal body and responsive to enzyme substrates or products present in said fluids; and a means for relating said response of said electrode means to the concentration of said enzyme substrates or products in said fluids.

Claim 3

An electrochemical cell sensor as defined in Claim 1 wherein said housing is a hollow needle composed of platinum or stainless steel and is covered with a layer of porous biocompatible material.

Claim 4

An electrochemical cell sensor capable of being implanted in an animal body comprising: an electrically conductive hollow needle housing with one or more openings in the walls of said electrically conductive hollow needle housing; an electrode means situated in said electrochemical when implanted, being cell sensor housing and, in fluid communication with fluids present in said animal body and responsive to enzyme substrates or products present in said fluids; means for differentially regulating the accessibility of said enzyme substrates to said electrode means; and a means for relating said response of said electrode means to the concentration of said enzyme substrates or products in said fluids.

Claim 5

An electrochemical cell sensor capable of being implanted in an animal body comprising: an electrically conductive hollow needle housing with one or more openings in the walls of said electrically conductive hollow needle housing; an electrode means situated in said electrochemical when implanted, being cell sensor housing and, in fluid communication with fluids present in said animal body and responsive to enzyme substrates or products present in said fluids; means for differentially regulating the accessibility of said enzyme substrates to said electrode means; and a means for relating said response of said electrode means to the concentration of said enzyme substrates or products in said fluids.

Claim 6

An electrochemical cell sensor as defined in Claim or 3 wherein said electrode means comprises four (4) electrodes: an enzyme substrate or product dependent sensing electrode composed of a noble metal and in communication with an oxidase enzyme, an enzyme substrate independent oxygen-sensing electrode composed of a noble metal, a reference electrode composed of silver/silver chloride, and a common counter electrode being said hollow needle housing.

Claim 7

5 . An electrochemical cell sensor as defined in Claims 3 and 4 wherein said means for differentially regulating the accessibility of said enzyme substrates comprises material with enzyme substrate selective diffusion properties situated over said opening or openings in said walls of said electrochemical cell structure hollow needle housing.

Claim 8

An electrochemical cell sensor as defined in Claims 3 and 4 wherein said material with enzyme substrate selective diffusion properties is less restrictive of the diffusion of oxygen than of other enzyme substrates.

Claim 9

7 . An electrochemical cell sensor as defined in Claim 4 wherein said means of regulating said response of said electrode means to the concentration of said enzyme substrates in said biological fluids is by an apparatus that measures the adjusted current output differential of said electrode means.

Claim 10

An electrochemical cell sensor as defined in Claim 4 wherein said means of relating said response of said electrode means to the concentration of said enzyme product in said fluids is by an apparatus that measures the adjusted current of the product sensing electrode and indicates said concentration of said enzyme substrate when the concentration of oxygen is sufficiently high as indicated by said second oxygen sensing electrode.

Claim 11

An electrochemical cell sensor capable of being implanted into an animal body comprising: a hollow needle housing with one or more openings in the walls of said housing, when implanted, being an electrode means situated in said housing and,/in fluid communication with fluids present in said animal body and responsive to said enzyme substrates present in said fluids, a means for supplying oxygen to said electrode means, and a means for relating said response of said electrode means to the concentration of said enzyme substrates in said biological fluids.

Claim 12

An electrochemical cell sensor capable of being implanted into an animal body comprising: a hollow needle housing with one or more openings in the walls of said housing, when implanted, being an electrode means situated in said housing and,/in fluid communication with fluids present in said animal body and responsive to said enzyme substrates present in said fluids, a means for supplying oxygen to said electrode means, and a means for relating said response of said electrode means to the concentration of said enzyme substrates in said biological fluids.

Claim 13

An electrochemical cell sensor as defined in Clairmg wherein said hollow needle housing is composed of platinum or stainless steel and is covered with a layer of porous biocompatible material.

Claim 14

An electrochemical cell sensor as defined in Clairmg wherein said hollow needle housing is composed of platinum or stainless steel and is covered with a layer of porous biocompatible material.

Claim 15

11 An electrochemical cell sensor as defined in Claim 9 wherein said electrode means comprises three (3) electrodes: an enzyme substrate or product dependent sensing electrode composed of a noble metal and in communication with an oxidase enzyme, a reference electrode composed of silver/silver chloride, and a common counter electrode being said hollow needle housing.

Claim 16

An electrochemical cell sensor as defined in Claim 4 or 11 wherein said the enzyme substrate dependent sensing electrode is polarized cathodically to determine oxygen.

Claim 17

13 . An electrochemical cell sensor as defined in Claim 4 or 11 wherein said enzyme product dependent sensing electrode is polarized anodically to determine hydrogen peroxide.

Claim 18

An electrochemical cell sensor as defined in Claim 9 wherein said means for supplying oxygen is a tunnel that provides communication of atmospheric oxygen with said electrode means.

Claim 19

An electrochemical cell sensor as defined in Claim 4 or 11 wherein said nonsensing areas of said electrode means are insulated.

Claim 20

An electrochemical cell sensor as defined in Claim 4, 11 or 15 wherein said oxidase enzyme is drawn from the group consisting of glucose oxidase, lactate oxidase, uricase, or alcohol oxidase.

Claim 21

An electrochemical cell sensor as defined in Claim 1, 3, 4 or 11 wherein said enzyme substrates are drawn from the group consisting of glucose, lactate, uricase, ethanol, or oxygen.