Zhao Xiaojun, Tapec-Dytioco Rovelyn, Tan Weihong
Department of Chemistry, McKnight Brain Institute, University of Florida, Gainesville, Florida 32611-7200, USA.
J Am Chem Soc. 2003 Sep 24;125(38):11474-5. doi: 10.1021/ja0358854.
Sensitive DNA detection is extremely important in clinical diagnostics, gene therapy, and a variety of biomedical studies. We have developed a novel DNA bioanalysis method with a 0.8 fM (0.8 x 10-15 M) detection limit using a bioconjugated fluorescent nanoparticle-based sandwich assay. An organic dye silica nanoparticle is synthesized using a modified reverse microemulsion. The nanoparticles are highly fluorescent, extremely photostable, and easy for bioconjugation for bioanalysis. They exhibit an excellent signaling ability in the presence of trace amounts of DNA targets. With an effective surface modification, nonspecific binding and nanoparticle aggregation are minimized. In addition, the nanoparticle-based DNA bioanalysis assay can effectively discriminate one-base mismatched DNA sequences. We expect this nanoparticle-based assay to be widely useful in a number of biomedical applications where reproducible, selective, and ultrasensitive gene analysis is critical.
灵敏的DNA检测在临床诊断、基因治疗以及各种生物医学研究中极为重要。我们开发了一种新型的DNA生物分析方法，采用基于生物共轭荧光纳米颗粒的夹心分析法，检测限为0.8 fM（0.8×10⁻¹⁵ M）。使用改良的反向微乳液合成有机染料二氧化硅纳米颗粒。这些纳米颗粒具有高荧光性、极高的光稳定性，并且易于进行生物共轭用于生物分析。在痕量DNA靶标的存在下，它们表现出出色的信号传导能力。通过有效的表面修饰，非特异性结合和纳米颗粒聚集被最小化。此外，基于纳米颗粒的DNA生物分析测定法可以有效区分单碱基错配的DNA序列。我们期望这种基于纳米颗粒的测定法在许多生物医学应用中广泛有用，在这些应用中，可重现、选择性和超灵敏的基因分析至关重要。
