Abstract
A method of the determination of serum iron binding capacity using radioiron and resin sponge was investigated. The resin sponge was supplied from Dainabott Laboratory as“Irosorb-59”Kit. One ml of serum was added to a plastic tube which contained 6 ig of iron labelled with59Feas ferric ammonium citrate. After 10 minutes of incubation, the resin sponge was added to the tube and pushed it by special stick in order to remove the air.59Feactivity in the tube was measured (A cpm) before incubation of 60 minutes at 37°C.
After the incubation, liquid layer was removed completely by suction using special designed stick. Two or 3 times of wash were repeated by distilled water with same procedure.59Feactivity of the sponge in the tube was counted (B cpm) .
Then
UIBC (μg/dl) =A-B×a*/A ×Fe (μg) ×100a* =absorption ratio
UIBC values obtained from Irosorb-59 method showed significant higher than the values obtained from magnesium carbonate. The elution of radioiron in sponge due to washing by water was negligible. The absorption rate of sponge to 6, cig of unbound iron on the presence of iron saturated serum was 78-88%.
59Felabelled ferric ammonium citrate was incubated to serum. After the treatment of sponge, the electrophoretic pattern of the serum was observed.59Feactivity existed chiefly inβ1-globulin fraction but lot of radioactivity also existed in albumin andα1-globulin fraction. From these results, ability of iron absorption of resin sponge seemed to be somewhat weaker than expected.
The treatment with 2 or 3 sponges to the same serum gave correct values of UIBC. Also, the use of corrected absorption ratio of resin sponge revealed moderately good results. However, in the serum which has very high or low UIBC, the values by this method showed somewhat different values compared with that of magnesium carbonate method. From the above results, it is concluded that this method is useful for the determination of UIBC in clinical samples.
