A Simple Preparation of Monoiodobromosulfophthalein-$^{131}$ I by Isotope Exchange for Medical Use

  • Published : 1977.03.01

Abstract

Monoiodobromosulfophthalein-$^{131}$ I (MIBSP-$^{131}$ I), one of the useful radiopharmaceuticals for liver function studies, has been prepared by a simple isotope exchange between the MIBSP and the molecular iodine-$^{131}$ I in phosphate buffer, pH 5.3. The pooled cold MIBSP was prepared by a normal iodination of BSP using iodine monochloride, and separated from the iodination mixture by applying a Sephadex LH-20 chromatography. At 10$0^{\circ}C$, the exchange rate was so fast that the reaction could be terminated in 5 min to show upto 95% yield. The final product could be obtained simply by further heating for about 5 min in a boiling water bath in the presence of a small amount of hydrogen peroxide, and subsequent pH adjustment and membrane filtration.

간장 질환 진단용 방사성 의약품인 $^{131}$ I 표지 1 요오드화 브로모프탈레인(MIBSP-$^{131}$ I)을 PH 5.3의 인삼염 완충용액에서 MIBSP와 $^{131}$ I$_2$의 동위원소 교환반응으로 제조할수 있음을 제시하였다. 비방사성 MIBSP는 브로모썰포프탈레인(BSP)을 IC1로 요오드화하고 나서 쎄파덱스 LH-20 크로마토그래피로 분리하여 얻었다. MIBSP와 $^{131}$ I의 동위원소 교환반응은 매우 빨리 일어나 10$0^{\circ}C$에서 5분안에 대략 95%의 표지수율을 보였다. 순수한 최종생성물 MIBSP-$^{131}$ I는 미량의 $H_2O$$_2$ 존재하에 약 5분간 더 반응시킨 후 PH를 조절하고 무균여과함으로써 간단히 얻어졌다.

Keywords