A sensitive fluorescence anisotropy method for the direct detection of cancer cells in whole blood based on aptamer-conjugated near-infrared fluorescent nanoparticles.
Based on the aptamer-conjugated core-shell near-infrared fluorescent nanoparticles (NIR-Nps) and fluorescence anisotropy measurement, the present study reported proof-of-principle for a rapid homogeneous assay approach that can detect target cancer cells without the need of the complicated separation steps in whole blood samples. Experimental investigation showed that the novel NIR-Nps have negligible background fluorescence and low inner filtration interference in complex biologic systems such as whole blood. The specific recognition characteristic of aptamer in whole blood samples was investigated by using the proposed fluorescence anisotropy method. The results showed that the fluorescent nanoparticle-tagged aptamer probes sequence could achieve specific recognition of the target cancer cells from complex mixtures including whole blood samples. And the reaction conditions for the binding between fluorescent nanoparticle-conjugated aptamer probes and target cancer cells were optimized. The present approach can exhibit sensitive and reproducible fluorescence anisotropy responses to the target cells concentration and the calibration curve showed good linearity when the target cells concentration is in the range from 4.0 x 10(3) to 7.0 x 10(5)cells/mL. Moreover, the present fluorescence anisotropy assay technique could be practically utilized for the detection of acute leukemia samples with improved capabilities and be comparable to the immunophenotyping methods clinically used.
Deng
Ting
T
Institute of Biological and Environmental Science & Technology, Central South University of Forestry and Technology, Changsha 410004, China.
Li
Jishan
J
Zhang
Liang-Liang
LL
Jiang
Jian-Hui
JH
Chen
Jie-Nan
JN
Shen
Guo-Li
GL
Yu
Ru-Qin
RQ
D016880:Anisotropy; D052157:Aptamers, Nucleotide; D045744:Cell Line, Tumor; D006801:Humans; D007938:Leukemia / Q000473:pathology*; D053758:Nanoparticles; D009360:Neoplastic Cells, Circulating / Q000473:pathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000379:methods*; D019265:Spectroscopy, Near-Infrared / Q000379:methods*
D052157:Aptamers, Nucleotide