Oura Shusuke, Ito Masahiro, Homma Yoshikazu, Umemura Kazuo
Department of Physics, Graduate School of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo, 1628601, Japan.
Eur Biophys J. 2018 Jul;47(5):523-530. doi: 10.1007/s00249-017-1269-8. Epub 2017 Nov 20.
In this study, we investigated the interaction of base sequence-assigned single-stranded DNA (ssDNA) molecules with the surfaces of single-walled carbon nanotube (SWNT)-thymine (T30)/cytosine (C30) hybrids (T30/C30-SWNT), by measuring the modulation of near-infrared (NIR) photoluminescence (PL). Significant PL shifts were observed when T30/C30-SWNTs were reacted with 30-mers of adenine (A30)/guanine (G30). In contrast, when non-complementary ssDNA was used, no significant energy shift was observed in the PL modulation except when T30-SWNTs were reacted with G30. Furthermore, atomic force microscopy (AFM) measurements revealed that the average heights of the T30-SWNTs and C30-SWNTs, after reaction with A30 were 2 ± 0.6 and 1.1 ± 0.3 nm, respectively. This result was in good agreement with the results of PL measurements. Our data reveal that DNA hybridization could be detected by measuring PL from SWNTs, without the use of fluorescent molecules. This leads to the possibility of developing nanotube-based photoelectric conversion or optical switch devices driven by organic molecules.
在本研究中，我们通过测量近红外（NIR）光致发光（PL）的调制，研究了碱基序列指定的单链DNA（ssDNA）分子与单壁碳纳米管（SWNT）-胸腺嘧啶（T30）/胞嘧啶（C30）杂化物（T30/C30-SWNT）表面的相互作用。当T30/C30-SWNTs与腺嘌呤（A30）/鸟嘌呤（G30）的30聚体反应时，观察到显著的PL位移。相比之下，当使用非互补ssDNA时，除了T30-SWNTs与G30反应外，在PL调制中未观察到明显的能量位移。此外，原子力显微镜（AFM）测量显示，与A30反应后，T30-SWNTs和C30-SWNTs的平均高度分别为2±0.6和1.1±0.3 nm。该结果与PL测量结果高度吻合。我们的数据表明，无需使用荧光分子，通过测量SWNTs的PL即可检测DNA杂交。这为开发由有机分子驱动的基于纳米管的光电转换或光开关器件提供了可能性。
