The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 15, 1984
Filed:
Jun. 18, 1982
Bruce P Neri, North Andover, MA (US);
Stanley M Liffmann, Methuen, MA (US);
Carolyn Bergkuist, Hampstead, NH (US);
Instrumentation Laboratory Inc., Lexington, MA (US);
Abstract
In a method for colorimetric determination of calcium, the sample to be analyzed is mixed with a dye reagent of pH value at which that reagent does not produce a predetermined change when complexed with calcium ions; a first colorimetric measurement is made on the mixture of the sample and dye reagent; a second reagent is added to the mixture of the sample and dye reagent to shift the pH and activate the dye reagent producing the predetermined change; and then a second colorimetric measurement is made on the resulting mixture, the difference between the two colorimetric measurements being a measure of calcium in the sample.