1 research outputs found
Enzyme-Catalyzed Oxidation Facilitates the Return of Fluorescence for Single-Walled Carbon Nanotubes
In this work, we
studied enzyme-catalyzed oxidation of single-walled
carbon nanotubes (SWCNTs) produced by the high-pressure carbon monoxide
(HiPco) method. While oxidation via strong acids introduced defect
sites on SWCNTs and suppressed their near-infrared (NIR) fluorescence,
our results indicated that the fluorescence of SWCNTs was restored
upon enzymatic oxidation, providing new evidence that the reaction
catalyzed by horseradish peroxidase (HRP) in the presence of H<sub>2</sub>O<sub>2</sub> is mainly a defect-consuming step. These results
were further supported by both UVāvisāNIR and Raman
spectroscopy. Therefore, when acid oxidation followed by HRP-catalyzed
enzyme oxidation was employed, shortened (<300 nm in length) and
NIR-fluorescent SWCNTs were produced. In contrast, upon treatment
with myeloperoxidase, H<sub>2</sub>O<sub>2</sub>, and NaCl, the oxidized
HiPco SWCNTs underwent complete oxidation (i.e., degradation). The
shortened, NIR-fluorescent SWCNTs resulting from HRP-catalyzed oxidation
of acid-cut HiPco SWCNTs may find applications in cellular NIR imaging
and drug delivery systems