School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China.
Chemistry. 2011 Sep 26;17(40):11230-6. doi: 10.1002/chem.201003010. Epub 2011 Aug 26.
An ultrasensitive and simple dynamic-light-scattering (DLS) assay for the sequence-specific recognition of double-stranded DNA (dsDNA) was developed based on detection of the average diameter change of Au nanoparticle (AuNP) probes modified with oligonucleotides 5'-TTTCTCTTCCTT- CTCTTC-(T)(12)-SH-3' (Oligo 1) and 5'-TTCTTTCTTTTCTTTTTC-(T)(12)- SH-3' (Oligo 2). The target dsDNA was composed of two complementary oligonucleotides: 5'-AAAGAGAAGGAAGAGAAGAAGAAAGAAAAGAAAAAG-3' (Oligo 3) and 3'-TTTCTCTTCCTTCTCTTCTTCTTTCTTTTCTTTTTC-5' (Oligo 4). Hybridization of the two AuNPs-Oligo probes with the target dsDNA induced aggregation of the target dsDNA by forming triplex DNA, which accordingly increased the average diameter. This diameter change could then be detected by DLS. The average diameter was proportional to the target dsDNA concentration over the range from 593 fM to 40 pM, with a detection limit of 593 fM. Moreover, the assay had good sequence specificity for the target dsDNA.
基于对经寡核苷酸 5′-TTTCTCTTCCTT- CTCTTC-(T)(12)-SH-3′（寡核苷酸 1）和 5′-TTCTTTCTTTTCTTTTTC-(T)(12)-SH-3′（寡核苷酸 2）修饰的金纳米颗粒（AuNP）探针平均直径变化的检测，开发了一种用于双链 DNA（dsDNA）序列特异性识别的超灵敏且简单的动态光散射（DLS）测定法。靶 dsDNA 由两条互补的寡核苷酸组成：5′-AAAGAGAAGGAAGAGAAGAAGAAAGAAAAGAAAAAG-3′（寡核苷酸 3）和 3′-TTTCTCTTCCTTCTCTTCTTCTTTCTTTTCTTTTTC-5′（寡核苷酸 4）。两个 AuNP-Oligo 探针与靶 dsDNA 的杂交通过形成三链 DNA 诱导靶 dsDNA 的聚集，从而相应地增加了平均直径。然后可以通过 DLS 检测这种直径变化。平均直径与靶 dsDNA 浓度呈正比，范围从 593 fM 到 40 pM，检测限为 593 fM。此外，该测定法对靶 dsDNA 具有良好的序列特异性。
