Method and apparatus for electrochemical analysis and an aqueous solution for use therein

An apparatus for electrochemical analysis, comprising:

• (a) an electrochemical sensor;
• (b) storage means for storing a first fluid;
• (c) storage means for storing a second fluid;
• (d) means for contacting said electrochemical sensor with a mixed sequence of first and second pluralities of samples and with said first and second fluids to measure the value of an analytical item in each said sample relative to the value thereof in said first fluid, said first and second pluralities having different respective analytical characteristics;
• (e) control means for controlling said contacting means, said control means being arranged to cause contact of said second fluid with said electrochemical sensor immediately prior to selected samples in said sequence and arranged to select said selected samples in dependence on the plurality to which the selected sample belongs and on the plurality to which the preceding sample in the sequence belongs.

An apparatus for electrochemical analysis of blood serum and urine, comprising:

• (a) an electrochemical sensor including at least one ion selective electrode for sensing ionic activity in blood serum and urine samples;
• (b) storage means for storing an internal standard solution;
• (c) storage means for storing an electrode response improving solution;
• (d) means for contacting said electrochemical sensor with a mixed sequence of blood serum samples and urine samples, and with said internal standard solution and said electrode response improving solution;
• (e) means for detecting and comparing outputs of said electrochemical sensor when contacted by said solutions and said samples, in order to measure the ionic activity in each said sample relative to the corresponding ionic activity of said internal standard solution;
• and
• (f) control means for controlling said contacting means, said control means being arranged to cause contact of said electrode response improving solution with said electrochemical sensor immediately prior to contact with said electrochemical sensor of each said urine sample in said sequence.

An apparatus for electrochemical analysis of blood serum and urine samples, comprising:

• (a) an electrochemical sensor;
• (b) storage means for storing a standard solution;
• (c) storage means for storing an electrode response improving solution;
• (d) means for contacting said electrochemical sensor with a group of blood serum samples and a group of urine samples in a sequence in which said blood serum samples and said urine samples are commonly arranged, and for contacting said electrochemical sensor with said standard solution and said electrode response improving solution to measure ionic activity in each said sample relative to the value of said ionic activity in said standard solution;
• (e) control means for controlling said contacting means, said control means being arranged to cause contact of said electrode response improving solution with said electrochemical sensor immediately prior to contact of each sample of one of said groups with said electrochemical sensor, and to cause contact of said standard solution with said electrochemical sensor immediately prior to contact of each sample of the other of said groups with said electrochemical sensor;
• and
• (f) said electrode response improving solution having a value of said ionic activity closer to the mean value of said ionic activity in said one of said group of samples than to said value of said ionic activity in said standard solution.