Abstract
A method for incorporating into proteins a nonradioactive Eu3+ label, which exhibits fluorescence of a long decay time in the presence of suitable ligands, is described. As an example of the use of this label the method has been developed to work as a sensitive protease assay. By hydrolyzing the Eu3+-labeled casein, bound to an insoluble matrix (Sepharose 4B or Affi-Gel 10), with proteases and measuring the Eu3+ released with a pulsed time-resolved fluorometer it was possible to detect as low as 2.5, 1.0, or 1.0 ng of alpha-chymotrypsin, trypsin, or subtilisin, respectively.
| Original language | English |
|---|---|
| Pages (from-to) | 399-403 |
| Number of pages | 5 |
| Journal | Journal of applied biochemistry |
| Volume | 5 |
| Issue number | 6 |
| Publication status | Published - Dec 1983 |
| Externally published | Yes |
| Publication type | A1 Journal article-refereed |
Keywords
- Animals
- Bacillus
- Cattle
- Chymotrypsin
- Europium
- Kinetics
- Microchemistry
- Pancreas
- Spectrometry, Fluorescence
- Subtilisins
- Swine
- Trypsin