title: Aptamer-conjugated nanoparticles for selective collection and detection of cancer cells.
abstract: We have developed a method for the rapid collection and detection of leukemia cells using a novel two-nanoparticle assay with aptamers as the molecular recognition element. An aptamer sequence was selected using a cell-based SELEX strategy in our laboratory for CCRF-CEM acute leukemia cells that, when applied in this method, allows for specific recognition of the cells from complex mixtures including whole blood samples. Aptamer-modified magnetic nanoparticles were used for target cell extraction, while aptamer-modified fluorescent nanoparticles were simultaneously added for sensitive cell detection. Combining two types of nanoparticles allows for rapid, selective, and sensitive detection not possible by using either particle alone. Fluorescent nanoparticles amplify the signal intensity corresponding to a single aptamer binding event, resulting in improved sensitivity over methods using individual dye-labeled probes. In addition, aptamer-modified magnetic nanoparticles allow for rapid extraction of target cells not possible with other separation methods. Fluorescent imaging and flow cytometry were used for cellular detection to demonstrate the potential application of this method for medical diagnostics.
authors.affiliation: Center for Research at the Bio/Nano Interface, Department of Chemistry and Shands Cancer Center, UF Genetics Institute and McKnight Brain Institute, University of Florida, Gainesville, Florida 32611, USA.
authors.forename: Joshua K
authors.initials: JK
authors.lastname: Herr
authors.forename: Joshua E
authors.initials: JE
authors.lastname: Smith
authors.forename: Colin D
authors.initials: CD
authors.lastname: Medley
authors.forename: Dihua
authors.initials: D
authors.lastname: Shangguan
authors.forename: Weihong
authors.initials: W
authors.lastname: Tan
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry*; D045744:Cell Line, Tumor; D002469:Cell Separation; D005434:Flow Cytometry / Q000379:methods; D005456:Fluorescent Dyes / Q000737:chemistry; D006801:Humans; D007938:Leukemia / Q000175:diagnosis*; D008280:Magnetics; D053758:Nanoparticles / Q000737:chemistry*; D052156:SELEX Aptamer Technique / Q000379:methods; D012680:Sensitivity and Specificity
chemical_list: D052157:Aptamers, Nucleotide; D005456:Fluorescent Dyes