Ahmad Ashraf, Kern Klaus, Balasubramanian Kannan
Max Planck Institute for Solid-State Research, Heisenbergstr. 1,70569 Stuttgart, Germany.
Chemphyschem. 2009 Apr 14;10(6):905-9. doi: 10.1002/cphc.200800796.
Highly selective: Enhancement of the photoluminescence (PL) emission efficiency of selected chiral forms of semiconducting single-walled carbon nanotubes (SWCNTs) is presented (see figure). Excitation of Nile blue A in the presence of SWCNTs results in the quenching of its fluorescence. The energy is resonantly transferred to the (7,5) SWCNT whereas the (8,7) tube is not in resonance; hence, its PL remains unaffected.We report on a simple method for enhancing the efficiency of photoluminescence (PL) emission from selected chiral forms of semiconducting single-wall carbon nanotubes (SWCNTs). The method is based on the use of a fluorescent dye (Nile blue A) that shows the capability of resonant energy transfer on to nanotubes. The excitation of Nile blue A in the presence of SWCNTs results in the quenching of its fluorescence and the energy is resonantly transferred to certain chiral forms. The PL emission from these chiral forms shows a marked increase in efficiency signifying the occurrence of Förster type resonant energy transfer (FRET). Due to its simplicity, this procedure has widespread implications for the detection of carbon nanotubes as well as for their use as fluorophores in FRET-based in vivo and in vitro biological applications.
本文展示了对半导体单壁碳纳米管（SWCNT）特定手性形式的光致发光（PL）发射效率的增强（见图）。在SWCNT存在的情况下激发尼罗蓝A会导致其荧光猝灭。能量共振转移到（7,5）SWCNT，而（8,7）管不发生共振；因此，其PL不受影响。我们报道了一种提高半导体单壁碳纳米管（SWCNT）特定手性形式的光致发光（PL）发射效率的简单方法。该方法基于使用一种荧光染料（尼罗蓝A），它具有将共振能量转移到纳米管上的能力。在SWCNT存在下激发尼罗蓝A会导致其荧光猝灭，并且能量共振转移到特定的手性形式。这些手性形式的PL发射显示出效率显著提高，表示发生了福斯特型共振能量转移（FRET）。由于其简单性，该方法对碳纳米管的检测以及它们在基于FRET的体内和体外生物应用中作为荧光团的使用具有广泛的意义。
