A fluorescence-based method for determining the surface coverage and hybridization efficiency of thiol-capped oligonucleotides bound to gold thin films and nanoparticles
A fluorescence-based method for determining the surface coverage and hybridization efficiency of thiol-capped oligonucleotides bound to gold thin films and nanoparticles
复制标题
DOI：
10.1021/ac0006627
复制
发表时间：
2000-11-15
影响因子：
7.4
通讯作者：
Viswanadham, G
中科院分区：
文献类型：
--
作者：
Demers, LM;Mirkin, CA;Viswanadham, G
使用基于荧光的方法，我们已经确定了与金纳米颗粒结合的巯基衍生化单链寡核苷酸的数量及其与溶液中互补寡核苷酸杂交的程度。己硫醇12聚体寡核苷酸在金纳米颗粒上的寡核苷酸表面覆盖率（34 +/- 1 pmol/cm（2））显著高于平面金薄膜（18 +/- 3 pmol/cm（2）），而金纳米颗粒上可杂交链的百分比（1.3 +/-0.3pmol/cm（2），4%）低于金薄膜（6 +/-2pmol/cm（2），33%）。在寡核苷酸沉积过程中电解质浓度的逐渐增加显著增加了表面覆盖率，并因此增加了颗粒稳定性。此外，寡核苷酸间隔序列提高了雷帕霉素修饰的纳米颗粒的杂交效率，从近似4到44%。识别链的表面覆盖率可以使用共吸附的稀释剂寡核苷酸来定制。这提供了间接控制每个纳米颗粒的杂交链的平均数目的手段。这里提出的工作具有重要的意义，关于了解修饰的寡核苷酸和金属纳米粒子之间的相互作用，以及优化基于金纳米粒子的寡核苷酸检测方法的灵敏度。
Using a fluorescence-based method, we have determined the number of thiol-derivatized single-stranded oligonucleotides bound to gold nanoparticles and their extent of hybridization with complementary oligonucleotides in solution. Oligonucleotide surface coverages of hexanethiol 12-mer oligonucleotides on gold nanoparticles (34 +/- 1 pmol/cm(2)) were significantly higher than on planar gold thin films (18 +/- 3 pmol/cm(2)), while the percentage of hybridizable strands on the gold nanoparticles (1.3 +/- 0.3 pmol/cm(2), 4%) was lower than for gold thin films (6 +/- 2 pmol/cm(2), 33%), A gradual increase in electrolyte concentration over the course of oligonucleotide deposition significantly increases surface coverage and consequently particle stability. In addition, oligonucleotide spacer sequences improve the hybridization efficiency of oligonucleotide-modified nanoparticles from similar to4 to 44%, The surface coverage of recognition strands can be tailored using coadsorbed diluent oligonucleotides. This provides a means of indirectly controlling the average number of hybridized strands per nanoparticle. The work presented here has important implications with regard to understanding interactions between modified oligonucleotides and metal nanoparticles, as well as optimizing the sensitivity of gold nanoparticle-based oligonucleotide detection methods.