Analytical element for theophylline determination using buffer in a subbing zone
US5028528A · kind A · utility
3Cited by
4References
9Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 25, 1988 |
| Grant date | Jul 2, 1991 |
| Priority date | — |
| Expiry date | Jul 25, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S436/825
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Theophylline can be determined with an analytical element and method which utilize the inhibition, by theophylline, of alkaline phosphatase activity on an appropriate substrate. The assay is carried out at a pH of 9 or less. The element comprises a porous spreading zone, a subbing zone and at least one other zone. The zones are in fluid contact with each other. The isoenzyme of alkaline phosphatase and a suitable substrate for the isoenzyme are located in different zones of the element. The subbing zone contains polyvinylpyrrolidone and a buffer for maintaining a pH of 9 or less.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.