SupplementaryInformation:
In vivoself-bio-imaging of tumors through in situbiosynthesized fluorescent gold nanoclusters
Jianling Wang,1 Gen Zhang,1 Qiwei Li,1 Hui Jiang,1 Chongyang Liu,3 Christian Amatore,2 Xuemei Wang*,1
1State Key Laboratory of Bioelectronics (Chien-Shiung Wu Lab), School of Biological Science and Medical Engineering, SoutheastUniversity, Nanjing, 210096, China
2 Ecole Normale Supérieure, UMR CNRS-ENS-UPMC 8640 and LIA CNRS XiamENS NanoBioChem Departement de Chimie, 24 rue Lhomond 75005 Paris (France)
3 Daping Hospital,ThirdMilitaryMedicalUniversity,Chongqing, 400042, China
The Supplementary Information includes:
Supplementary Figures S1-S5
Supplementary Figures
Figure S1|MTT assay assessment of dose-dependent cytotoxicity towards cells (A: HepG2 cells and B: L02 cells) 48 h after incubation with HAuCl4 solutions and in situ biosynthesis of gold nanoclusters with incubation for 48 h.
Figure S2|Laser confocal fluorescence micrographs of leukemia K562 cells after incubation during 24 h with 10 μmol/L HAuCl4. Images were acquired at 400-fold magnification. The inset shows an enlarged view of a single cell.
Figure S3|Laser confocal fluorescence micrographs of HepG2 cells after incubation for 24 h with 10 μmol/L HAuCl4. (A, C) Fluorescence micrograph; (B) Overlay of morphological and fluorescence images; (C) Fluorescence tomography image along a plane perpendicular to bottom of HepG2 cells (slice thickness: 0.75 µm).
Figure S4|Characterization of the gold nanoclusters biosynthesized in situ by HepG2 cells after for 24 h with 10 μmol/L HAuCl4. (A) TEM image of the gold nanoclusters, showing the ~0.2 nminterplanar spacing of the gold nanoclusters (inset).(B) Optical characterization of the gold nanoclusters. Curve a shows the UV/Vis absorption spectrum of the relevant gold nanoclusters; curve b shows their fluorescence emission spectrum (Em) at a 470-nm excitation wavelength (their excitation spectrum (Ex) is shown in the inset).
Figure S5|X-ray photoelectron spectra (XPS) of Au 4f for gold nanoclusters.
Figure S6| (A) Raman spectrum of HepG2 cells after 48 h-incubation with 10 μmol/L HAuCl4, subtracted by that of HepG2 cells recorded before incubation. (B) Enlargement of the spectrum in (A) over the range 1000–1800 cm-1. Excitation wavelength: 532 nm.
The prominent Raman spectra of HepG2 cells evidenced that the biosynthesized gold nanoclustersinteracted with biomolecules (Figure S6) as evidenced by the SERS enhancing and changes incurred by proteins and DNA Raman bands. In proteins, the amide IIIband (1200–1300 cm-1; Figure S6)1which is sensitive to the mainchainconformation resultedred-shifted and increased in intensity indicating a close interaction with biosynthesized gold nanoclusters. Conversely, the bands at about 1002,1449and 1172 cm-1, whichbelongto symmetric ring breathing mode of phenylalanine, CH2 bending mode of proteins and C–H in-plane bending mode of tyrosine, respectively,2 werealmost unchanged. Concerning DNA, little change could be observed for the bands at about 783, 724 and 824cm-1which reflects nucleotide (cytosine/uracil, adenine) ring breathing and the symmetric telescopic vibration of PO2 (BNPP), respectively.3On the contrary,the telescopic vibration intensity of thymine C=Oincreased at 1666 cm-1, and the intensity of the purine bases(i.e., guanine and adenine) bands at 1335 cm-1and 1582 cm-1increased and shifted to 1331 cm-1 and1573 cm-1, respectively,testifying an interaction with the gold nanoclusters.
Figure S7|Xenograft tumor mouse models ofhepatocellular carcinomaobserved by in vivo fluorescence imaging (A: 24 h and B: 72h) after a subcutaneous injection of 10 mmol/L HAuCl4 solution near the tumor.
Supplementary Reference
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