Development of a halloysite nanotube-based 19 F NMR probe as a promising detection tool for H 2 O 2

The 19F nuclear magnetic resonance (NMR) has been widely employed as a detection tool in biological studies due to its low biological background, noninvasiveness, high sensitivity, and real-time monitoring capability. Herein, we report a one-pot synthesis of halloysite nanotubes (HNTs) treated with benzeneboronic acids (6FBB) to afford the HNT-based 19F NMR probe which is capable to detect the H2O2 in low concentration. The product was well characterized by nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FTIR), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). The intensity of signals of 19F was enhanced with the increasing concentration of fluorine, and the signals apparently shifted from − 62.68 to − 62.85 ppm upon the addition of H2O2. The obtained 19F NMR probes also displayed a long spin-spin (T2) relaxation time (91.27 ms), which can strengthen image intensity. Moreover, the 19F NMR probe exhibited non-toxic against HeLa cell. The 19F NMR probe may serve as a desirable candidate to predict the change of H2O2 in vivo.