Orlanducci Silvia, Fulgenzi Gianluca, Margonelli Andrea, Rea Giuseppina, Antal Taras K, Lambreva Maya D
Department of Chemical Science and Technology, University of Rome ''Tor Vergata'', 00133 Rome, Italy.
Institute of Crystallography, National Research Council of Italy, 00015 Monterotondo Stazione, Italy.
Materials (Basel). 2020 Nov 13;13(22):5121. doi: 10.3390/ma13225121.
Carbon nanotubes (CNTs) are among the most exploited carbon allotropes in the emerging technologies of molecular sensing and bioengineering. However, the advancement of algal nanobiotechnology and nanobionics is hindered by the lack of methods for the straightforward visualization of the CNTs inside the cell. Herein, we present a handy and label-free experimental strategy based on visible Raman microscopy to assess the internalization of single-walled carbon nanotubes (SWCNTs) using the model photosynthetic alga as a recipient. The relationship between the properties of SWCNTs and their biological behavior was demonstrated, along with the occurrence of excitation energy transfer from the excited chlorophyll molecules to the SWCNTs. The non-radiative deactivation of the chlorophyll excitation promoted by the SWCNTs enables the recording of Raman signals originating from cellular compounds located near the nanotubes, such as carotenoids, polyphosphates, and starch. Furthermore, the outcome of this study unveils the possibility to exploit SWCNTs as spectroscopic probes in photosynthetic and non-photosynthetic systems where the fluorescence background hinders the acquisition of Raman scattering signals.
碳纳米管（CNTs）是分子传感和生物工程等新兴技术中应用最为广泛的碳同素异形体之一。然而，藻类纳米生物技术和纳米仿生学的发展受到细胞内碳纳米管直接可视化方法缺乏的阻碍。在此，我们提出一种基于可见拉曼显微镜的简便且无标记的实验策略，以模式光合藻类为受体来评估单壁碳纳米管（SWCNTs）的内化情况。研究证明了单壁碳纳米管的性质与其生物学行为之间的关系，以及激发态叶绿素分子到单壁碳纳米管的激发能转移现象。单壁碳纳米管促进的叶绿素激发的非辐射失活使得能够记录来自纳米管附近细胞化合物（如类胡萝卜素、多磷酸盐和淀粉）的拉曼信号。此外，本研究结果揭示了在荧光背景阻碍拉曼散射信号采集的光合和非光合系统中，利用单壁碳纳米管作为光谱探针的可能性。
