@article{oai:kanazawa-u.repo.nii.ac.jp:00058971,
 author = {三代, 憲司 and 柴, 和弘 and 絹谷, 清剛 and 小川, 数馬 and Effendi, Nurmaya and Mishiro, Kenji and Shiba, Kazuhiro and Kinuya, Seigo and Ogawa, Kazuma},
 issue = {1},
 journal = {Molecules},
 month = {},
 note = {The purpose of this study is to develop peptide-based platelet-derived growth factor receptor β (PDGFRβ) imaging probes and examine the effects of several linkers, namely un-natural amino acids (D-alanine and β-alanine) and ethylene-glycol (EG), on the properties of Ga-DOTA(linker)-IPLPPPRRPFFK peptides. Seven radiotracers,67 Ga-DOTA-(linker)-IPLPPPRRPFFK peptides, were designed, synthesized, and evaluated. The stability and cell uptake in PDGFRβ positive peptide cells were evaluated in vitro. The biodistribution of [67 Ga]Ga-DOTA-EG2-IPLPPPRRPFFK ([67 Ga]27) and [67 Ga]Ga-DOTA-EG4-IPLPPPRRPFFK ([67 Ga]28), which were selected based on in vitro stability in murine plasma and cell uptake rates, were determined in BxPC3-luc-bearing nu/nu mice. Seven67 Ga-labeled peptides were successfully synthesized with high radiochemical yields (>85%) and purities (>99%). All evaluated radiotracers were stable in PBS (pH 7.4) at 37◦ C. However, only [67 Ga]27 and [67 Ga]28 remained more than 75% after incubation in murine plasma at 37◦ C for 1 h. [67 Ga]27 exhibited the highest BxPC3-luc cell uptake among the prepared radiolabeled peptides. As regards the results of the biodistribution experiments, the tumor-to-blood ratios of [67 Ga]27 and [67 Ga]28 at 1 h post-injection were 2.61 ± 0.75 and 2.05 ± 0.77, respectively. Co-injection of [67 Ga]27 and an excess amount of IPLPPPRRPFFK peptide as a blocking agent can significantly decrease this ratio. However, tumor accumulation was not considered sufficient. Therefore, further probe modification is required to assess tumor accumulation for in vivo imaging. © 2020 by the authors. Licensee MDPI, Basel, Switzerland. This., CC-BY 4.0, 金沢大学疾患モデル総合研究センター},
 title = {Development of radiogallium-labeled peptides for platelet-derived growth factor receptor β (Pdgfrβ) imaging: Influence of different linkers},
 volume = {26},
 year = {2021}
}