Supporting Information for

Transcription

1 Supporting Information for Direct Fluorescent Detection of Blood Potassium by Ion-selective Formation of Intermolecular G-quadruplex and Ligand Binding Le Yang, Zhihe Qing,, * Changhui Liu, Qiao Tang, Jishan Li, Sheng Yang, Jing Zheng, Ronghua Yang,,, * Weihong Tan State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, College of Chemistry and Chemical Engineering, Molecular Science and Biomedicine Laboratory, Changsha 8, P. R. China. School of Chemistry and Biological Engineering, Changsha University of Science and Technology, Changsha, P. R. China. *To whom correspondence should be addressed: Yangrh@pku.edu.cn; qingzhihe@hnu.edu.cn Fax:

2 Table S. Oligonucleotides used in this study. Type G-quad Oligo- Oligo- Oligo- Oligo- Oligo- Oligo- Sequence '-TGAGGGTGGGGAGGGTGGGGAA-' '-TGAGGGTGGGG-' '-AGGGTGGGGAA-' '-TGAGGGAGGGG-' '-GAGGGTGGGGT-' '-AGGGTGGGGTG-' '-TGAGGGAGGGG-'-'-T-' -Brom obutyric acid ethyl ester DMF, KI, KOH -vinylpyridine Palladium(II) acetate Tri-o-tolyl phosphine CH CN/TEA N N CH I N DMF, CH CN O (EBMVC-B) OEt Figure S. Synthetic route for EBMVC-B.

3 CD / mdeg mm [K + ] - 7 Figure S. The change of circular dichroism spectrum of oligo-, as a function of increasing K + concentration in Tris-HCl buffer ( mm, ph 7.). The concentration of oligo- is fixed at µμ.

4 Normalized fluorescence. G-quad : EBMVC-B oligo-. : +G-quad : +Na. : +K oligo- : EBMVC-B : +oligo- : +Na + : +K + : +Na + : +K + oligo-.... oligo- : EBMVC-B oligo-. : +oligo- : EBMVC-B : +oligo- : +Na + : +K + : EBMVC-B : +oligo- : +Na + : +K + : EBMVC-B : +oligo- : +Na + : +K Figure S. Normalized fluorescence responses of EBMVC-B in Tris-HCl buffer ( mm, ph 7.) to. mm K + or mm Na + when different G-rich DNAs were used as the recognition element. The concentration for EBMVC-B is. µm, and DNAs are at nm. The maximal signal for each case is normalized as..

5 . / (CD-CD )... y =.x +.87 R = / [K + ] (mm - ) Figure S. Double reciprocal plot between /(CD-CD ) and /[K + ], where CD is the initial circular dichroism intensity of oligo- at nm, CD is that with addition of different concentrations of K +, and [K + ] indicates K + concentration. The concentration of oligo- is µm.

6 . µm. µm Fluorescence( ) [oligo-]. Fluorescence( ) [oligo-] (C) F / F [oligo-] / µm Figure S. Optimization of oligo- concentration for K + detection. A) Fluorescence spectra corresponding to different concentrations of oligo- in the absence of K + ; B) Fluorescence spectra corresponding to different concentrations of oligo- in the presence of. mm K + ; C) Demonstration through signal-to-background ratio (F/F ), where F is the fluorescence intensity of the detection system at 7 nm in the absence of K +, F is that in the presence of. mm K +. The concentration for EBMVC-B is. µm, buffer ph is 7., and the operation temperature is fixed at o C.

7 ph. ph 7. ph. ph 7. Fluorescence( ) ph 7. ph 7.8 ph 8. Fluorescence( ) ph 7. ph 7.8 ph (C) F / F ph Figure S. Optimization of buffer ph for K + detection. A) Fluorescence spectra corresponding to different ph in the absence of K + ; B) Fluorescence spectra corresponding to different ph in the presence of. mm K + ; C) Demonstration through signal-to-background ratio (F/F ), where F is the fluorescence intensity of the detection system at 7 nm in the absence of K +, and F is that in the presence of mm K +. The concentrations for EBMVC-B and oligo- are. µm and.µm, respectively, and the operation temperature is fixed at o C. 7

8 Fluorescence( ) o C o C o C o C o C Fluorescence( ) o C o C o C o C o C (C) F / F Temperature / o C Figure S7. Optimization of temperature for K + detection. A) Fluorescence spectra corresponding to different temperature in the absence of K + ; B) Fluorescence spectra corresponding to different temperature in the presence of. mm K + ; C) Demonstration through signal-to-background ratio (F/F ), where F is the fluorescence intensity of the detection system at 7 nm in the absence of K +, and F is that in the presence of mm K +. The concentrations for EBMVC-B and oligo- are. µm and.µm, respectively, and ph is fixed at 7.. 8

9 Fluorescence( ) mm [K + ] 7 7 Figure S8. Fluorescence emission spectra of the oligo-/ebmvc-b detection system with the addition of K + under similar physiological electrolyte condition ( mm Na +, mm Mg +, mm Ca + and. µm Pb + ). The arrow marks K + concentration increasing from - mm. The concentrations for EBMVC-B and oligo- are. µm and.µm, respectively, in Tris-HCl buffer ( mm, ph 7.). 9

10 Fluorescence ( ) Fluorescence ( ) (C). Normalized intensity.8... oligo- oligo-. 8 Time / h Figure S9. Fluorescence spectra of oligo-/ebmvc-b and oligo-/ebmvc-b when incubated in % calf serum for different time; C) fluorescence change (at 7 nm) of oligo-/ebmvc-b and oligo-/ebmvc-b after incubation. Before incubation, oligo-/ebmvc-b and oligo-/ebmvc-b are mixed with mm K + for hours, respectively, and the relative fluorescence intensity is defined as (F-F b )/(F - F b ), where F b is the background fluorescence intensity of % calf serum, F is the fluorescence intensity at the start of incubation, and F is that at the corresponding time point.

11 Fluorescence ( ) : EBMVC-B+oligo- : +mm K + : +mm Na + : +mm Na + +mm K + Fluorescence ( ) : EBMVC-B+oligo- : +mm K + : +mm Na + : +mm Na + +mm K Figure S. Fluorescence spectra of EBMVC-B under different conditions when naked oligo-, or the inverted thymine nucleotide-modified oligo-, is used as the recognition element. The concentrations for EBMVC-B, oligo- and oligo- are.,. and. µm, respectively, in Tris-HCl buffer ( mm, ph 7.).

12 Fluorescence ( ) : % DMEM : +oligo-/ebmvc-b Fluorescence : % DMEM : +EBMVC-B/oligo- 7 Figure S. A) One-photon-excited and B) two-photon-excited fluorescence spectra of the cell culture media (DMEM) before and after addition of oligo-/ebmvc-b. The concentrations for EBMVC-B and oligo- are. and. µm, respectively.

13 Fluorescence ( ) 8 : % human plasma : +EBMVC-B/oligo- Fluorescence : % human plasma : +EBMVC-B/oligo- 7 Figure S. A) One-photon-excited and B) two-photon-excited fluorescence spectra of the human plasma before and after addition of oligo-/ebmvc-b. The concentrations for EBMVC-B and oligo- are. and. µm, respectively.