Studies on 90YCl3 Colloid for Clinical Use

90Y is a high-energy radioisotope and emite β-ray with 2.6 days half life. 90YCl3 colloid has been used for malignant tumor therapeutically, as 198Au colloid.In the present experiment, the purification of 90Y, and the detection of the contaminated 90Sr was studied. Amberlite XE-100 column was suitable for this prupose. The colloidal size of 90YCl3 was transformed by pH, and the features of 90YCl3 colloids were observed on electrone microscope.1) 90Y and 90Sr mixture adsorbed on Amberlite XE-100 column (100-200 mesh, 2.5 column volume), and eluted by 0.5N HCl. 90Sr is eluted out at 10-60ml, and 90Y is eluted out from 170ml.2) A mixture of 20mC of citrate-90Y complex and 1μC of 90Sr fixed on this column, and then eluted by 0.5N HCl. One drop of eluate at 10ml was detectable by GM counter. The detectable lower limit of contaminated 90Sr is 0.1μC by re-counting on GM counter 24hrs after the elution.3) Amberlite XE-100 column is suitable for the second column on the milking system, for the purpose of separating the contaminated 90Sr and 90Y. This procedure is complete in 1hr process.4) 90YCl3 colloid is aggregated and formed clamp in high pH solution, Electrone microscopic observations showed that the colloidal size was 40-50mμ at pH 5, and 20mμ at pH 7.