title: Incorporation of quantum dots on virus in polycationic solution.
abstract: Developing methods to label viruses with fluorescent moieties has its merits in elucidating viral infection mechanisms and exploring novel antiviral therapeutics. Fluorescent quantum dots (QDs), an emerging probe for biological imaging and medical diagnostics, were employed in this study to tag retrovirus encoding enhanced green fluorescent protein (EGFP) genes. Electrostatic repulsion forces generated from both negatively charged retrovirus and QDs were neutralized by cationic Polybrene, forming colloidal complexes of QDs-virus. By examining the level of EGFP expression in 3T3 fibroblast cells treated with QDs-tagged retroviruses for 24 hours, the infectivity of retrovirus incorporated with QDs was shown to be only slightly decreased. Moreover, the imaging of QDs can be detected in the cellular milieu. In summary, the mild method developed here makes QDs-tagged virus a potential imaging probe for direct tracking the infection process and monitoring distribution of viral particles in infected cells.
authors.affiliation: Department of Chemical Engineering, University of Southern California, Los Angeles, CA 90089-1211, USA. jyou@usc.edu
authors.forename: Jin-Oh
authors.initials: JO
authors.lastname: You
authors.forename: Yu-San
authors.initials: YS
authors.lastname: Liu
authors.forename: Yu-Chuan
authors.initials: YC
authors.lastname: Liu
authors.forename: Kye-Il
authors.initials: KI
authors.lastname: Joo
authors.forename: Ching-An
authors.initials: CA
authors.lastname: Peng
mesh_terms: D000818:Animals; D002412:Cations; D049452:Green Fluorescent Proteins; D051379:Mice; D008856:Microscopy, Fluorescence / Q000379:methods*; D041681:NIH 3T3 Cells; D045663:Quantum Dots; D012190:Retroviridae / Q000737:chemistry / Q000302:isolation & purification / Q000648:ultrastructure*; D013194:Staining and Labeling / Q000379:methods*
chemical_list: D002412:Cations; D049452:Green Fluorescent Proteins