US 4,233,031 A · Electrochemical testing system and method

Abstract

An electrochemical measuring system which effects, measures and sorts charge transfer reactions of selected substances in a sample solution is provided. The system includes a novel electrode which is adapted to measure simultaneously on at least two electrodes at least two electolytic potentials with reference to a reference potential. In a preferred form the electrode comprises a hollow, cylindrical body formed of an electrically insulating material. The electrode is open at least at one end and has a generally smooth cylindrical inner surface. A plurality of electrically discrete active electrode segments are mounted on the inner surface of the electrode with their active surfaces substantially flush with the generally smooth cylindrical inner surface. Completing the electrochemical measuring system are a stirring means for creating a relatively high degree of mixing adjacent the electrode active surfaces, means for charging liquid samples to the cell, and means connecting at least two of the electrically discrete active electrode segments to different electrical potentials. In use a sample to be tested is charged to the cell, and stirring is commenced. One of the electrically discrete active electrode sgements is held at a potential at which a selected substance of interest and also one or more interferring substances responds, while another of the electrode segments is held at a potential at which only the interferring substances respond. The presence of a substance of interest can be determined by subtracting the signals from the one and another electrode segments, and its quantity determined by integrating the signal difference.

Claims44

Dependent claims

In serum iron testing, a method of electrochemical testing compatible with micro sized samples of serum comprising:

preparing a substantially iron-free matrix including a lower aliphatic alcohol and between about 51/2 Formal and about 81/2 Formal HCl;
introducing a predetermined quantity of serum into said matrix to provide an electrolytic sample, and adding a measured quantity of said sample containing a measured quantity of serum to an electrolytic cell;
applying to a first electrode in said cell a potential to measure the quantity of copper and iron in said cell;
applying to a second electrode in said cell a potential to measure a different quantity selected from copper and iron;
obtaining signals corresponding to current flow at each of said electrodes;
and
comparing said signals to measure the quantity of iron.

4 more elements

Apparatus for electrochemical testing of serum iron comprising:

(a) support means;
(b) a cell block positioned on said support means and including an electrolytic cell to contain a quantity of a sample serum;
(c) an electrode body in said cell having a plurality of electrically discrete active testing electrode segments and at least one reference electrode segment, at least a first said active testing electrode segment being adapted to detect and measure a first quantity corresponding to both iron and copper, and at least a second active testing electrode segment being adapted to detect and measure a different quantity selected from iron and copper, whereby the quantity of iron can be determined by comparing the electrochemical measures of said electrode segments;
(d) means to apply to said first active testing electrode segment a potential for measuring both iron and copper from serum;
(e) means to apply to said second active testing electrode segment a potential for measuring a different quantity selected from iron and copper;
(f) means to compare signals corresponding to electric currents to said first and second active testing electrode segments to determine, by said comparison, the quantity of iron in said sample.

3 more elements

Apparatus for electrochemical testing of serum iron comprising:

(a) support means;
(b) a cell block positioned on said support means and including an electrolytic cell to contain a quantity of a sample of serum;
(c) an electrode body in said cell having a plurality of electrically discrete active electrode segments and at least one reference electrode segment, at least a first of said active testing electrode segments being adapted to detect and measure both iron and copper, and at least a second of said active testing electrode segments being adapted to detect and measure a different quantity selected from iron and copper, whereby the quantity of iron can be determined by comparing the electrochemical measures of said active testing electrode segments;
(d) stirring means in said cell;
(e) sample input means to receive a measured quantity of a serum sample for testing;
(f) input means to introduce electrolyte liquid to said cell;
(g) outlet means to discharge electrolyte from said cell;
(h) means to supply electrolyte liquid to said cell and to discharge electrolyte through said outlet means;
(i) means to apply to said first active testing electrode segment a potential for measuring both iron and copper from serum;
(j) means to apply to said second active testing electrode segment a potential for measuring a different quantity selected from iron and copper;
and
(k) means to compare signals corresponding to electric currents to said first and second active testing electrodes to determine, by said comparison, the quantity of iron in said sample.

9 more elements

Dependencies are inferred from the claim text.

Electrochemical testing system and method

Life of this patent

Electrochemical testing system and method

Life of this patent

Abstract

Claims44