Supporting Information. A Fluorogenic Resveratrol-Confined Graphene Oxide For Economic and Rapid. Detection Of Alzheimer's Disease

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1 Supporting Information A Fluorogenic Resveratrol-Confined Graphene Oxide For Economic and Rapid Detection Of Alzheimer's Disease Xiao-Peng He, 1 Qiong Deng, 1 Liang Cai, 1 Chang-Zheng Wang, 1,2 Yi Zang,*,2 Jia Li,*,2 Guo-Rong Chen,*,1 and He Tian 1 1 Key Laboratory for Advanced Materials & Institute of Fine Chemicals, East China University of Science and Technology, 130 Meilong Rd., Shanghai , PR China; 2 National Center for Drug Screening, State Key Laboratory of Drug Research, Shanghai Institute of MateriaMedica, Chinese Academy of Sciences, 189 GuoShoujing Rd., Shanghai , P. R. China Contents list: S1. Experimental section S2. Fig.S1 and Fig. S3 S3. Cost estimation

2 S1. Experimental section 1.1. General All reagents and solvents are of high purity and used as purchased. All UV-vis absorption spectra were recorded with a Varian Cary 500 UV-vis spectrophotometer and fluorescence spectra with a Varian Cary Eclipse Fluorescence spectrophotometer Preparation of Res@GO GO (purchased from XFNANO, China) was suspended in water with an initial concentration of 2 mg/ml. Res (20 μm, purchased from Sgma-Aderich) was dissolved in PBS (0.2 M, ph 7.4) and then mixed with GO of different concentrations. The mixture was sonicated for 10 s and then incubated for 5 min at room temperature before analyses Atomic force microscope (AFM) Morphology study was performed with an AFM (AJ-III, Aijian nanotechnology Inc., China) in air under tapping mode at room temperature. The samples used were dispersed on freshly cleaved mica and then dried at room temperature Raman spectroscopy Raman spectra were performed on a RenishawInVia Reflex Raman system (Renishawplc, Wotton-under-Edge, UK) employing a grating spectrometer with a Peltier-cooled charge-coupled device (CCD) detector coupled to a confocal microscope, which were then processed with RenishawWiRE 3.2 software. The Raman scattering was excited by an argon ion laser (I = nm).

3 1.5. Fluorescence spectroscopy All fluorescent spectra were recorded with an excitation of 310 nm, and the emission was scanned from 300nm to 600 nm. Aβ peptides or proteins were incubated with the in PBS (0.2 M, ph 7.4). The resulting mixture was incubated at room temperature for 3 min before the fluorescence intensity was recorded Fourier transform infrared (FTIR) spectroscopy FTIR spectra were recorded on a Nicolet 3 FTIR spectrometer (Thermo Electron Corporation, USA). The samples were mixed with KBr and then compressed into pellets for analysis in the spectral range of ν = 4000 to 400 cm -1. All baselines of the spectra were corrected Imaging of AD mouse brain slice with Res@GO The brain sections of transgenic mice carrying APPswe/PS1dE9 mutations (APP/PS1 mice) were fixed in 4% paraformaldehyde in PBS overnight and processed for paraffin embedding. 3.5 μm sections were cut using a rotary microtome. Paraffin-embedded sections were deparaffinized and rehydrated. Sections were then treated with 3% H 2 O 2 in PBS for 10 min, followed by blocking with 5% bovine serum albumin in PBS for 30 min. The sections were then incubated with rabbit polyclonal primary antibody against β-amyloid (CST,#2454) diluted at 1:100 in blocking buffer overnight at 4 C. After which sections were washed in PBS and incubated with TRITC-labeled anti-rabbit secondary antibodies diluted at 1:100 in blocking buffer for 1 h. Finally, sections were stained with Res (20 μm )@Go(50 μg/ml ) composite in PBS for 30 min, mounted with cover slips and imaged using an Olympus microscope.

4 1.8. WST-8 Viability Assay Cell viability was measured using a cell counting kit-8 (CCK-8, Dojindo, Rockville, MD) cells were seeded in a 96-well plate and cultured in HG-DMEM supplemented with 10% FBS and 1% PS at 37 C under 5% CO 2. After 10 h, the cells were washed with 100 μl of serum-free HGDMEM (1% PS) two times and incubated with 100 μl of different concentrations of Res@GO in serum-free HGDMEM (1% PS). After 24 h exposure, the cells were washed twice with serum-free HGDMEM and 10 μl of CCK-8 solution was added to each well containing 100 μl of serum-free HGDMEM, followed by a gentle shake. After 3 h incubation at 37 C under 5% CO 2, μl of the mixture was transferred to another 96-well plate (because residual GO can affect the absorbance values at 450 nm). The absorbance of the mixture solutions was measured at 450 nm with 655 nm as a reference, using an M5 microplate reader (Molecular Device, USA). (Reference: Liao, et al., ACS Appl. Mater. Interfaces, 2011, 3, 2607.)

5 S2. Fig. S1 and Fig. S3 a b 75 T (a.u.) T (a.u.) c Wavelength (cm -1 ) Wavelength (cm -1 ) 75 T (a.u.) Wavelength (cm -1 ) Figure S1. FTIR spectra of (a) resveratrol, (b) graphene oxide, and (c) Res@GO.

6 a b FL (a.u.) Concentration (μm) Concentration (μm) c d FL (a.u.) Concentration (μm) Concentration (μm) Figure S2. The linear range of fluorescence change of Res@GO in the presence of increasing (a) Aβ42 monomer, (b) Aβ42 fibril,(c) Aβ40 monomer, and (d) Aβ40 fibril in phosphate buffered saline (0.2 M, ph 7.4) with excitation at 310 nm.

7 150 %viability µm Res µg/ml Go 6.25 µm Res µg/ml Go 25 µm Res+62.5 µg/ml Go 50 µm Res+125 µg/ml Go 100 µm Res+250 µg/ml Go Figure S3. Cytotoxicity of Res@GO at different concentrations for HEK293.

8 S3. Cost estimation Considering only the price of the primary anti-aβ antibody (2972 RMB for 100 μl from Cell Signal) and the fluorescently tagged secondary antibody (2225 RMB for 500 μl from Invitrogen) used, the cost of the immunofluorescence technique for staining 100 mouse brain slices is estimate to be roughly 1500 RMB (30 μl of 100 primary antibody and 30 μl of 200 secondary antibody consumed per slice). Note that other expenses are not considered. Considering only the price of GO (purchased from XFNANO, 200 RMB for 20 ml, concentration: 2mg/mL) and Res (purchased from Sigma-Alderich, 7 RMB/mg). The cost of the present protocol for staining 100 mouse brain slices is estimated to be roughly 0.85 RMB [30 μl of Res (20 μm)@go (50 μg/ml) consumed per slice]. Note that other expenses are not considered.