Degradation or excretion of quantum dots in mouse embryonic stem cells.
BACKGROUND
Quantum dots (QDs) have been considered as a new and efficient probe for labeling cells non-invasively in vitro and in vivo, but fairly little is known about how QDs are eliminated from cells after labeling. The purpose of this study is to investigate the metabolism of QDs in different type of cells.


RESULTS
Mouse embryonic stem cells (ESCs) and mouse embryonic fibroblasts (MEFs) were labeled with QD 655. QD-labeling was monitored by fluorescence microscopy and flow cytometry for 72 hours. Both types of cells were labeled efficiently, but a quick loss of QD-labeling in ESCs was observed within 48 hours, which was not prevented by inhibiting cell proliferation. Transmission electron microscope analysis showed a dramatic decrease of QD number in vesicles of ESCs at 24 hours post-labeling, suggesting that QDs might be degraded. In addition, supernatants collected from labeled ESCs in culture were used to label cells again, indicating that some QDs were excreted from cells.


CONCLUSIONS
This is the first study to demonstrate that the metabolism of QDs in different type of cells is different. QDs were quickly degraded or excreted from ESCs after labeling.
Pi
Qing Meng
QM
Department of Plastic and Reconstructive Surgery, Shanghai 9th People's Hospital, Shanghai Jiao Tong University School of Medicine, National Tissue Engineering Center of China, Shanghai, China.
Zhang
Wen Jie
WJ
Zhou
Guang Dong
GD
Liu
Wei
W
Cao
Yilin
Y
D000818:Animals; D002460:Cell Line; D049109:Cell Proliferation; D002470:Cell Survival; D053595:Embryonic Stem Cells / Q000378:metabolism*; D005434:Flow Cytometry; D051379:Mice; D046529:Microscopy, Electron, Transmission; D008856:Microscopy, Fluorescence; D045663:Quantum Dots; D013194:Staining and Labeling
Anal Biochem. 2004 Apr 15;327(2):200-8
15051536
Small. 2006 Dec;2(12):1412-7
17192996
Biomaterials. 2006 Mar;27(8):1656-64
16188313
Eur J Pharm Biopharm. 2008 Feb;68(2):153-68
17869074
Expert Opin Drug Metab Toxicol. 2008 Jan;4(1):1-15
18370855
FEBS Lett. 2004 Jun 1;567(1):116-20
15165903
Science. 2002 Nov 29;298(5599):1759-62
12459582
Nat Biotechnol. 2003 Jan;21(1):47-51
12459736
Dev Dyn. 2007 Dec;236(12):3393-401
17626285
Biochem Biophys Res Commun. 2003 Mar 14;302(3):496-501
12615061
Ann Biomed Eng. 2006 Jan;34(1):3-14
16450199
Mini Rev Med Chem. 2006 Dec;6(12):1383-9
17168814
Cancer Biomark. 2008;4(6):307-19
19126959
Nat Mater. 2005 Jun;4(6):435-46
15928695
Differentiation. 2006 Mar;74(2-3):81-90
16533307
BMC Biotechnol. 2007 Oct 09;7:67
17925032
Nano Lett. 2004 Jan 1;4(1):11-18
28890669
Anal Bioanal Chem. 2008 Aug;391(7):2469-95
18548237
Basic Res Cardiol. 2006 Jul;101(4):301-10
16705471
Biotechniques. 2003 Feb;34(2):296-300, 302-3
12613252
IEEE Trans Nanobioscience. 2009 Mar;8(1):65-71
19304503
Biotechnol Lett. 2008 Aug;30(8):1409-14
18415052
Stem Cells. 2008 Jul;26(7):1713-22
18436861
J Nanosci Nanotechnol. 2008 Mar;8(3):1019-51
18468106
Stem Cells. 2007 Aug;25(8):2128-38
17495112
Chembiochem. 2008 May 23;9(8):1251-9
18435448
J Nanobiotechnology. 2007 Nov 07;5:9
17988386
Methods Enzymol. 2003;365:186-202
14696346