Lin Nay San, Kitamura Masaki, Saito Makoto, Hirayama Kota, Ide Yuki, Umemura Kazuo
Department of Physics, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo 1628601, Japan.
ACS Omega. 2022 Aug 8;7(33):28896-28903. doi: 10.1021/acsomega.2c02038. eCollection 2022 Aug 23.
In this study, two biomolecule solutions were distinguished using the capacity difference in the near-infrared photoluminescence (PL) of single-walled carbon nanotubes (SWNTs). Biosensing techniques using sensitive responses of SWNTs have been intensively studied. When a small amount of an oxidant or reductant solution was injected into the SWNT suspensions, the PL intensity of the SWNTs is significantly changed. However, distinguishing between different molecules remains challenging. In this study, we comparably injected saponin and banana solutions, which are known antioxidant chemicals, into an SWNT suspension. The SWNTs were solubilized by wrapping them with DNA molecules. The results show that 69.1 and 155.2% increases of PL intensities of SWNTs were observed after injection of 20 and 59 μg/mL saponin solutions, respectively. Subsequently, the increase in PL was saturated. With the banana solution, 18.1 and 175.4% increases in PL intensities were observed with 20 and 59 μg/mL banana solutions, respectively. Based on these results, the two antioxidant molecules could be distinguished based on the different PL responses of the SWNTs. In addition, the much higher saturated PL intensities observed with the banana solution suggests that the banana solution increased the capacity of the PL increase for the same SWNT suspension. These results provide helpful information for establishing biosensing applications of SWNTs, particularly for distinguishing chemicals.
在本研究中，利用单壁碳纳米管（SWNTs）近红外光致发光（PL）的容量差异区分了两种生物分子溶液。利用SWNTs的敏感响应的生物传感技术已得到深入研究。当将少量氧化剂或还原剂溶液注入SWNT悬浮液中时，SWNTs的PL强度会发生显著变化。然而，区分不同分子仍然具有挑战性。在本研究中，我们将已知的抗氧化剂化学物质皂苷和香蕉溶液相对地注入SWNT悬浮液中。通过用DNA分子包裹SWNTs使其溶解。结果表明，分别注入20和59μg/mL皂苷溶液后，SWNTs的PL强度分别增加了69.1%和155.2%。随后，PL的增加达到饱和。对于香蕉溶液，分别用20和59μg/mL香蕉溶液时，PL强度分别增加了18.1%和175.4%。基于这些结果，可以根据SWNTs不同的PL响应区分这两种抗氧化分子。此外，香蕉溶液观察到的更高的饱和PL强度表明，对于相同的SWNT悬浮液，香蕉溶液增加了PL增加的能力。这些结果为建立SWNTs的生物传感应用，特别是区分化学物质提供了有用的信息。
