@article {Shetty1921, author = {Dinesh Shetty and Jae Min Jeong and Chang Ju and Young Kim and Yun Lee and Dong Lee and June Chung and Myung Lee}, title = {68Ga-labeled alanine derivatives as a novel PET agent for cancer imaging}, volume = {50}, number = {supplement 2}, pages = {1921--1921}, year = {2009}, publisher = {Society of Nuclear Medicine}, abstract = {1921 Objectives Various amino acids labeled with 18F and 11C for PET are used. However, they require expensive cyclotron and complicate synthesis procedure. We developed alanine derivatives, NOTA-ala and DOTA-ala, for labeling with 68Ga, a generator nuclide. Methods Protected β-amino-L-alanine was synthesizedstarting from tBoc-L-serine methyl ester by mesyl protection, azide formation and catalytic reduction. And then it was conjugated to NOTA and DOTA in aqueous solution using EDC as a coupling agent. Protecting groups were removed by lithium hydroxide (4 eq) and hydrochloric acid (30\%), successively. The final products were obtained as HCl salts by HPLC purification. DOTA-ala (26.3 {\textmu}g) and NOTA-ala (21.3 {\textmu}g) were labeled with 68Ga in pH 3.7~5.2. Labeling efficiencies were checked by ITLC. Biodistribution and PET imaging studies were performed using balb/c mice xenografted with CT-26. Results Both DOTA-ala and NOTA-ala were labeled with 68Ga in high yields (\>98\%). In biodistribution study, tumor uptakes were 3.3 and 2.9\% ID/g at 10 min and 2.8 and 2.5\% ID/g at 60 min for 68Ga-DOTA-ala and 68Ga-NOTA-ala, respectively. The tumor to muscle and tumor to blood uptake ratio showed significantly higher value for 68Ga-NOTA-ala than 68Ga-DOTA-ala. Micro PET images for both labeled compounds showed a high bladder activity at 1 h. High uptakes were found in tumors along with kidney on 2 h images comparing to other organs. Conclusions We synthesized 68Ga labeled amino acid derivatives for tumor PET which can be labeled by one step reaction within 10 min. The NOTA-ala derivatives showed high tumor uptakes in biodistribution and animal PET studies.}, issn = {0161-5505}, URL = {https://jnm.snmjournals.org/content/50/supplement_2/1921}, eprint = {https://jnm.snmjournals.org/content}, journal = {Journal of Nuclear Medicine} }