Dilute lattice doping of Cu into 2D-nanoplates: its impact on radio-labeling efficiency and stability for target selective PET imaging

• Published in: Journal of materials chemistry. B, Materials for biology and medicine Vol. 1; no. 45; pp. 9389 - 9399
• Main Authors: Eom, Sairan, Kim, Min Hwan, Yoo, Ranji, Choi, Goeun, Kang, Joo Hyun, Lee, Yong Jin, Choy, Jin-Ho
• Format: Journal Article
• Published: 23.11.2022
• ISSN: 2050-750X; 2050-7518
• DOI: 10.1039/d2tb01165d

A quintinite nanoplate ( 64 Cu-QT-NP) isomorphically substituted with 64 Cu, as the positron emission tomography (PET) imaging material, was prepared via two-step processes. A 64 Cu labeling efficiency of 99% was realized, for the first time, by immobilizing the 64 Cu radioisotope directly in the octahedral site of the 2-dimensional (2D) quintinite lattice. Furthermore, the 64 Cu labeling stability of 64 Cu-QT-NPs was also achieved to be more than ∼99% in various solutions such as saline, phosphate-buffered saline (PBS), and other biological media (mouse and human serums). In an in vivo xenograft mouse model, the passive targeting behavior of 64 Cu-QT-NPs into tumor tissue based on the enhanced permeability and retention (EPR) effect was also demonstrated by parenteral administration, and successfully visualized using a PET scanner. For enhancing the tumor tissue selectivity, bovine serum albumin (BSA) was coated on 64 Cu-QT-NPs to form 64 Cu-QT-NPs/BSA, resulting in better colloidal stability and longer blood circulation time, which was eventually evidenced by the 2-fold higher tumor uptake rate when intravenousely injected in an animal model. It is, therefore, concluded that the present 64 Cu-QT-NPs/BSA with tumor tissue selectivity could be an advanced nano-device for radio-imaging and diagnosis as well. The designed 64 Cu-QT-NPs, where 64 Cu radioisotopes were isomorphically doped in the octahedral site of the QT lattice, were showed high labeling efficiency and stability, and selectively targeted to the tumor tissue due to the passive targeting effect.