Use of a sparingly soluble salt of a heteropoly acid for the determination of an analyte, a corresponding method of determination as a suitable agent therefor

• US 5,240,860 A
• Filed: 12/03/1990
• Issued: 08/31/1993
• Est. Priority Date: 12/02/1989
• Status: Expired due to Term

• Current Assignee: Boehringer Mannheim GmbH Federal Republic of Germany
• Original Assignee: Boehringer Mannheim GmbH (Roche Holding AG)
• Inventors: Unkrig, Volker, Hoenes, Joachim, Wielinger, Hans
• Primary Examiner(s): Robinson, Douglas W.
• Assistant Examiner(s): Weber, Jon P.
• Application Number:
  US07/620,697
• Time in Patent Office: 1,002 Days
• Field of Search: 436/111, 436/112, 436/113
• US Class Current: 436/111
• CPC Class Codes: C12Q 1/00 Measuring or testing processes involving enzymes, nucleic acids or microorganisms measuring or testing apparatus with condition measuring or sensing means, e.g. colony counters, C12M1/34; Compositions therefor; Processes of preparing such compositions
• CPC Class Codes: C12Q 1/26 involving oxidoreductase
• CPC Class Codes: C12Q 1/34 involving hydrolase
• CPC Class Codes: C12Q 1/48 involving transferase
• CPC Class Codes: G01N 33/48 Biological material, e.g. blood, urine G01N33/02, G01N33/26, G01N33/44, G01N33/46 take precedence; Haemocytometers counting blood corpuscules distributed over a surface by scanning the surface G06M11/02
• CPC Class Codes: G01N 33/525 Multi-layer analytical elements
• CPC Class Codes: Y10T 436/173845 Amine and quaternary ammonium
• CPC Class Codes: Y10T 436/174614 Tertiary amine
• CPC Class Codes: Y10T 436/175383 Ammonia

Abstract

A sparingly soluble salt of a heteropoly acid is used for the determination of an analyte which is an aromatic amine rich in electrons or together with another substance leads to such an amine. The analyte is determined by means of the heteropoly blue color formed.

Claims

1. A method for the colorimetric determination of an electron-rich aromatic amine which is a stronger reducing agent than aniline and has a redox potential of less than 0.6 volts, which comprises the steps of contacting the electron-rich aromatic amine with a sparingly soluble salt of a heteropoly acid and determining the presence of the electron-rich aromatic amide by detecting heteropoly blue formation.

2. A method according to claim 1, wherein the heteropoly acid is a heteropoly acid of molybdenum, molybdenum and tungsten, vanadium and molybdenum or vanadium, molybdenum and tungsten with phosphorus, arsenic, silicon or germanium as the heteroatoms.

3. A method according to claim 2, wherein the heteropoly acid is 18-molybdodiphosphoric acid.

4. A method according to claim 1, wherein the cation of the sparingly soluble salt of the heteropoly acid is larger than NH₄⁺.

5. A method according to claim 4, wherein the cation is of the formula R¹ R² R³ R⁴ X⁺, in which R¹, R¹, R², R³, and R⁴ are the same or different and denote hydrogen, or an alkyl, aryl, or aralkyl residue or two alkyl residues may be taken together to form an alkylene residue, and X represents a phosphorus or a nitrogen atom, provided that all of R¹, R², R³, and R⁴ are not hydrogen.

6. A method according to claim 5, wherein X is a nitrogen atom.

7. A method according to claim 1, wherein the amine has the formula II ##STR2## in which R⁵ denotes hydroxy or amino, in which the amino group is unsubstituted or substituted once or twice by a C_1-6 alkyl residue, and the alkyl residue is itself unsubstituted or substituted by a hydroxy group, PO₃ H₂, SO₃ H, CO₂ H, or an amino group unsubstituted or substituted once or twice by C_1-6 alkyl, and R⁶ and R⁷ which independently represent hydrogen or C_1-6 alkyl, in which the alkyl residue is unsubstituted or substituted by a hydroxy group, PO₃ H₂, SO₃ H, CO₂ H, or an amino group unsubstituted or substituted once or twice by C_1-6 alkyl, and R⁸, R⁹, R¹⁰, and R¹¹ are independently hydrogen, C_1-6 alkyl, C_1-6 alkoxy, C_1-6 alkylthio, C_6-10 aryloxy, C_6-10 arylthio, halogen, carboxy, carboxy-C_1-6 alkyl or C_1-6 alkoxycarbonyl.

8. A method for colorimetric determination of an analyte which comprises the steps of reacting the analyte with at least one substance which is converted to or forms an electron-rich aromatic amine which is a stronger reducing agent than aniline and has a redox potential of less than 0.6 volts, thereafter contacting the electron-rich aromatic amine so formed with a sparingly soluble salt of a heteropoly acid capable of forming heteroblue with the said amine and determining the presence of the electron-rich aromatic amine by detecting heteropoly blue formation.

9. A method according to claim 8, wherein the amount of heteropoly blue formed is measured.

10. A method according to claim 8, wherein the heteropoly acid is a heteropoly acid of molybdenum, molybdenum and tungsten, vanadium and molybdenum or vanadium, molybdenum and tungsten with phosphorus, arsenic, silicon or germanium as the heteroatoms.

11. A method according to claim 8, wherein the analyte is an enzyme.

12. A method according to claim 8, wherein the substance is hydrolyzed to form the amine.

13. A method according to claim 8, wherein the cation of the sparingly soluble salt of the heteropoly acid is larger than NH₄⁺ and is of the formula R¹ R² R³ R⁴ X⁺, in which R¹, R², R³, and R⁴ are independently hydrogen, or an alkyl, aryl, or aralkyl residue, or two alkyl residues may be taken together to form an alkylene residue, and X represents a phosphorus or a nitrogen atom, and provided that all of R¹, R², R³, and R⁴ are not hydrogen.

14. A method according to claim 8, wherein the amine has the formula II ##STR3## in which R⁵ denotes hydroxy or amino, in which the amino group is unsubstituted or substituted once or twice by a C_1-6 alkyl residue, and the alkyl residue is itself unsubstituted or substituted by a hydroxy group, PO₃ H₂, SO₃ H, CO₂ H, or an amino group unsubstituted or substituted once or twice by C_1-6 alkyl, and R⁶ and R⁷ which are independently hydrogen or C_1-6 alkyl, in which the alkyl residue is unsubstituted or substituted by a hydroxy group, PO₃ H₂, SO₃ H, CO₂ H, or an amino group unsubstituted or substituted once or twice by C_1-6 alkyl, and R⁸, R⁹, R¹⁰, and R¹¹ are independently hydrogen, C_1-6 alkyl, C_1-6 alkoxy, C_1-6 alkylthio, C_6-10 aryloxy, C_6-10 arylthio, halogen, carboxy, carboxy-C_1-6 alkyl or C_1-6 alkoxycarbonyl.