Institute of Biological and Environmental Science & Technology, Central South University of Forestry and Technology, Changsha 410004, China.
Biosens Bioelectron. 2010 Mar 15;25(7):1587-91. doi: 10.1016/j.bios.2009.11.014. Epub 2009 Nov 20.
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.
基于适体偶联的核壳近红外荧光纳米粒子（NIR-Nps）和荧光各向异性测量，本研究报告了一种快速均相测定方法的原理验证，该方法可在无需全血样本中复杂分离步骤的情况下检测靶癌细胞。实验研究表明，新型 NIR-Nps 在全血等复杂生物体系中具有可忽略的背景荧光和低内滤光干扰。通过使用所提出的荧光各向异性方法研究了适体在全血样本中的特异性识别特性。结果表明，荧光纳米粒子标记的适体探针序列可以从包括全血样本在内的复杂混合物中实现对靶癌细胞的特异性识别。并优化了荧光纳米粒子偶联适体探针与靶癌细胞结合的反应条件。本方法对靶细胞浓度表现出灵敏且可重复的荧光各向异性响应，并且当靶细胞浓度在 4.0 x 10(3)至 7.0 x 10(5)个细胞/mL 的范围内时，校准曲线具有良好的线性。此外，本荧光各向异性测定技术可实际用于检测急性白血病样本，具有增强的能力，并且可与临床使用的免疫表型测定方法相媲美。
