Preparation of 125I-protein A usable for up to 10 months in immunoassays
Research output: Contribution to journal › Journal article › Research › peer-review
Chloramine-T iodination of protein A from Staphylococcus aureus and gel electrophoretic purification of the iodination mixture results in a stable tracer of high specific and functional activity. Following repeated gel electrophoresis of the tracer only a single component was observed. The specific activity of the 125I-protein A was between 30 and 55 muCi/micrograms. The binding of 125I-protein A to rabbit immunoglobulin exceeded 90% and the tracer competed effectively with unlabelled protein A in binding to cells incubated with sera containing surface antibodies. Storage of the tracer for up to 46 weeks resulted in a moderate decrease in maximal binding to immunoglobulin (from 91% to 64%), in TCA precipitable radioactivity (from 97% to 80%) and an approx. 30% decrease in the ability to detect cell bound immunoglobulin. It is concluded that gel electrophoretic purification of 125I-protein A produces a tracer with a very long shelf life.
Original language | English |
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Journal | Journal of Immunological Methods |
Volume | 71 |
Issue number | 2 |
Pages (from-to) | 193-201 |
Number of pages | 9 |
ISSN | 0022-1759 |
Publication status | Published - 6 Jul 1984 |
- Chloramines, Electrophoresis, Polyacrylamide Gel, Iodine Radioisotopes, Isotope Labeling, Staphylococcal Protein A, Tosyl Compounds
Research areas
ID: 132900976