PT  - JOURNAL ARTICLE
AU  - Schipper, Meike L.
AU  - Cheng, Zhen
AU  - Lee, Sheen-Woo
AU  - Bentolila, Laurent A.
AU  - Iyer, Gopal
AU  - Rao, Jianghong
AU  - Chen, Xiaoyuan
AU  - Wu, Anna M.
AU  - Weiss, Shimon
AU  - Gambhir, Sanjiv S.
TI  - microPET-Based Biodistribution of Quantum Dots in Living Mice
AID  - 10.2967/jnumed.107.040071
DP  - 2007 Sep 01
TA  - Journal of Nuclear Medicine
PG  - 1511--1518
VI  - 48
IP  - 9
4099  - http://jnm.snmjournals.org/content/48/9/1511.short
4100  - http://jnm.snmjournals.org/content/48/9/1511.full
SO  - J Nucl Med2007 Sep 01; 48
AB  - This study evaluates the quantitative biodistribution of commercially available CdSe quantum dots (QD) in mice. Methods: 64Cu-Labeled 800- or 525-nm emission wavelength QD (21- or 12-nm diameter), with or without 2,000 MW (molecular weight) polyethylene glycol (PEG), were injected intravenously into mice (5.55 MBq/25 pmol QD) and studied using well counting or by serial microPET and region-of-interest analysis. Results: Both methods show rapid uptake by the liver (27.4–38.9 %ID/g) (%ID/g is percentage injected dose per gram tissue) and spleen (8.0–12.4 %ID/g). Size has no influence on biodistribution within the range tested here. Pegylated QD have slightly slower uptake into liver and spleen (6 vs. 2 min) and show additional low-level bone uptake (6.5–6.9 %ID/g). No evidence of clearance from these organs was observed. Conclusion: Rapid reticuloendothelial system clearance of QD will require modification of QD for optimal utility in imaging living subjects. Formal quantitative biodistribution/imaging studies will be helpful in studying many types of nanoparticles, including quantum dots.