• 대한핵의학회:학술대회논문집
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• 1997.05a
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• pp.185-185
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• 1997

• The Korean Journal of Nuclear Medicine
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• v.32 no.3
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• pp.290-297
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• 1998

Purpose : The aim of this study was to evaluate the feasibility of 3-[$^{131}I$]iodo-O-methyl-L-${\alpha}$-methyltyrosine ([$^{131}I$]OMIMT) as an agent for tumor image. Materials and Methods : After synthesis of 4-O-methyl-L-${\alpha}$-methyltyrosine (OMAMT), OMAMT was labeled with [$^{131}I$] using Iodogen method. In vitro cellular uptake study was performed using 9 L gliosarcoma cells at various time points upto 4 hr. The biodistribution (five rats implanted with the 9 L gliosar-coma cells per group) was evaluated at 30 min, 2 hr, 24 hr after iv injection of 3.7 MBq [$^{131}I$]OMIMT or L-3-[$^{131}I$]iodo-${\alpha}$-methyltyrosine [$^{131}I$]IMT). Gamma camera images were obtained at 30 min, 2 hr and 24 hr. Results: [$^{131}I$]OMIMT uptake was 3.3 times and 2.5 times higher than [$^{131}I$]IMT uptake at 30 min and 60 min, respectively and same after 2 hr in in vitro study using 9L gliosarcoma cells. Maximum accumulation in tumor occurred at 30 min for both [$^{131}I$]OMIMT and [$^{131}I$]IMT in tumor bearing rats. The tumor uptake of [$^{131}I$]OMIMT was significantly higher than that of [$^{131}I$]IMT at early time point studied ($3.74{\pm}0.48$ vs $0.38{\pm}0.17%$ ID/g at 30 min and $2.40{\pm}0.17$ vs $0.24{\pm}0.03%$ ID/g at 2 hr, respectively, p<0.01). However, the tumor uptake of both radiolabels were not significantly different at 24 hr ($0.04{\pm}0.01$ vs $0.05{\pm}0.01%$ ID/g). Tumor was visualized as early as at 30 min in gamma camera images. Conclusion: These data suggested that [$^{131}I$]OMIMT might be a useful tumor imaging agent and has more advantage for the tumor imaging compared to [$^{131}I$]IMT

• The Korean Journal of Nuclear Medicine
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• v.29 no.1
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• pp.105-109
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• 1995

L-3-[$^{123}I$]iodo-${\alpha}$-methyltyrosine([$^{123}I$] IMT) was synthesized by electrophilic radio-iodination using chloramine-T and Iodobead in phosphate buffered solution. And the biodistribution was examined in 9L glioma bearing rats. The radiosynthesis of [$^{123}I$]IMT with iodobead was simpler and higher in radiochemical yield(88%) than the method using chloramine-T(83%) as radioiodinating reagent. The highest yield was obtained from the reaction using 1 piece of Iodobead, $200{\mu}g$ ${\alpha}$-methyltyrosine in $100{\mu}l$ phosphate-buffered solution(pH 5.5) and the reaction was completed in 7min. 24 hours after the injection, the biodistribution in 9L glioma transplanted rats revealed the in vivo deiodination, the excretion via kidney, and 3 times higher uptake in the tumor than normal brain. These results suggest the promising clinical use of [$^{123}I$] IMT in the various malignancies.