Colorimetric method and reagent for the assay of lithium in a test sample
US5187103A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 31, 1991 |
| Grant date | Feb 16, 1993 |
| Priority date | — |
| Expiry date | Jan 31, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N33/84
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A chromogenic cryptand found to be especially selective in the determination of lithium in blood of the general formula (I): ##STR1## where: n=1 or 2, PA0 R.sub.1 and R.sub.2, same or different, are hydrogen, lower alkyl, lower alkenyl, or lower alkylidene; and PA0 Q is a chromogenic moiety capable of providing a detectable response upon complexation of said compound with lithium ion and has the structure: ##STR2## wherein: X is CH, C--OH or N; and Z is p-nitrophenylazo, 2,4-dinitrophenylazo, 2,4,6-trinitrophenylazo, p-nitrostyryl, p-benzoquinonemonoimino, bis-(4-dimethylaminophenyl) hydroxymethyl, 3-phenylisothiazolyl-5-azo, thiazolyl-5-azo; or isothiazolyl-5-azo. A reagent composition and synthesis of a preferred chromogenic cryptand are also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.