Boronlectin/polyelectrolyte Ensembles as Artificial Tongue: Design, Construction and Application for Discriminative Sensing of Complex

Transcription

1 Supporting Information Boronlectin/polyelectrolyte Ensembles as Artificial Tongue: Design, Construction and Application for Discriminative Sensing of Complex Glycoconjugates from Panax ginseng Xiao-tai Zhang, Shu Wang and Guo-wen Xing* Department of Chemistry, Beijing Normal University, Beijing , China. Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing , China S-1

2 1. Synthesis Scheme S1. Synthetic routes of a) FBA1, b) FBA2, c) FBA3, d) FBA4. S-2

3 Scheme S2. Synthetic route of fluorescent indicators IA and IB. S-3

4 2. Figures and Tables a) Fluorescence intensity (a.u.) 1.5x x x x x [FBA1] µm Wavelength (nm) b) Fluorescence Intensity (a.u.) 1.5x x x x x [FBA2] 0 30 µm Wavelength (nm) c) Fluorescence Intensity (a.u.) 1.5x x x x x [FBA3] 0 20 µm Wavelength (nm) d) Fluorescence Intensity (a.u.) 1.5x x x x x [FBA4] 0 6 µm Wavelength (nm) Figure S1. Fluorescence spectra of the indicator IA (10 µm) upon addition of a) FBA1, b) FBA2, c) FBA3 and d) FBA4, measured in 10 mm ph 7.4 phosphate buffer. [IA] = 10 µm, λ ex = 421 nm. S-4

5 a) Fluorescence Intensity (a.u.) 1.8x x x x x x [FBA1] 0 60 µm Wavelength (nm) b)1.8x10 6 Fluorescence Intensity (a.u.) 1.5x x x x x [FBA2] 0 10 µm Wavelength (nm) c)1.8x10 6 Fluorescence Intensity (a.u.) 1.5x x x x x [FBA3] 0 10 µm Wavelength (nm) d)1.8x10 6 Fluorescence Intensity (a.u.) 1.5x x x x x [FBA4] 0 5 µm Wavelength (nm) Figure S2. Fluorescence spectra of the indicator IB (10 µm) upon addition of a) FBA1, b) FBA2, c) FBA3 and d) FBA4, measured in 10 mm ph 7.4 phosphate buffer. [IB] = 10 µm, λ ex = 408 nm. S-5

6 a) F 0 /F at 466 nm F 0 /F at 466 nm [FBA] (µm) [FBA] (µm) FBA1 FBA2 FBA3 FBA4 b) F 0 /F at 526 nm FBA1 FBA2 FBA3 FBA4 F 0 /F at 526 nm [FBA] (µm) [FBA] (µm) Figure S3. Quenching plots of a) IA and b) IB with the increase of FBAs concentrations. Insets: the linear relationship between fluorescence responses and the low concentration of FBAs. IA: λ ex = 421 nm, λ em = 466 nm; IB: λ ex = 408 nm, λ em = 526 nm. F 0 : initial fluorescence intensity of the indicators, F: fluorescence intensity upon addition of the quenchers. Absorbance [FBA4] 0 6 µm Wavelength (nm) Figure S4. UV-Vis absorption spectra of IA upon addition of FBA4 as the quencher. S-6

7 a) Effective Diameter (nm) IA only Intensity % Size (nm) IA/FBA1 IA/FBA2 IA/FBA3 IA/FBA4 b) Effective Diameter (nm) IB only Intensity % Size (nm) IB/FBA1 IB/FBA2 IB/FBA3 IB/FBA4 Figure S5. Effective particle diameters of a) IA (10 µm) and IA (10 µm)/fba (5 µm) ensembles, b) IB (10 µm) and IB (10 µm)/fba (3 µm) ensembles. Insets: the distributions of particle sizes. Particle sizes were measured by dynamic light scattering (DLS). The effective particle diameter of the system with IA solely was measured to be 280 nm (Figure S5a). Introduction of FBA1 or FBA2 at the concentration of 5 µm made the particle diameters increase to above 350 nm, since the concentration of quenchers within the linear quenching range conduced a predominant swelling effect through inserting into the existing aggregates consisted of IA (Figure S6). However, the same concentration of FBA3 or FBA4 corresponded to superlinear quenching was proved to bring about an apparent shrink effect, and consequently the particle diameters decreased to below 220 nm, suggesting the formation of the tighter aggregates. The same phenomena also exhibited in the IB-related systems (Figure S5b). Figure S6. Schematic drawing of the swelling and shrink effect. S-7

8 Figure S7. The TEM images of a) IA, b) FBA4, c) IA/FBA4 (n/n = 10:1), d) IA/FBA4 (n/n = 10:3), e) IA/FBA4 (n/n = 2:1). The micromorphology changed from amorphous structures (for IA or FB4) to meshy structures upon the formation of IA/FBA4 complex IA only Absorbance IA/FBA4 IA/FBA4/Rb Wavelength (nm) Figure S8. UV-Vis absorption spectra of IA (10 µm) (black line), IA (10 µm)/fba4 (5 µm) ensemble (red line) and IA (10 µm)/fba4 (5 µm)/rb1 (2 mm) mixture (blue line) in 10 mm ph 7.4 phosphate buffer containing 2% DMSO. S-8

9 a) Fluorescence Intensity (a.u.) 1.8x x x x x x IA only IA / FBA1 IA /FBA1/sucrose IA /FBA2 IA /FBA2/sucrose IA / FBA3 IA /FBA3/sucrose IA/ FBA4 IA /FBA4 /sucrose Wavelength (nm) b) F presence /F absence at 466 nm IA/FBA1 /sucrose IA/FBA2 /sucrose IA/FBA3 /sucrose IA/FBA4 /sucrose y = 1 Figure S9. a) Fluorescence emission spectra of IA (10 µm) (black solid line), IA (10 µm)/fba (5 µm) emsembles (the other solid lines) and IA (10 µm)/fba (5 µm)/sucrose (10 mm) mixtures (dashed lines). b) The relative fluorescence changes in the presence of 10 mm sucrose. S-9

10 a) F/F 0 at 466 nm IA/FBA1 IA/FBA2 IA/FBA3 IA/FBA [Rb1] (mm) b) F/F 0 at 466 nm 1.5 IA/FBA1 IA/FBA2 1.4 IA/FBA3 IA/FBA [Rb3] (mm) c) F/F 0 at 466 nm 1.30 IA/FBA IA/FBA2 IA/FBA IA/FBA [Rd] (mm) d) F/F 0 at 466 nm 1.4 IA/FBA1 IA/FBA2 IA/FBA3 1.3 IA/FBA [Rg1] (mm) e) F/F 0 at 466 nm IA/FBA1 IA/FBA2 IA/FBA3 IA/FBA [Re] (mm) Figure S10. Relative fluorescence recovery of IA/FBA ensembles upon addition of a) Rb1, b) Rb3, c) Rd, d) Rg1 and e) Re (7 replicates), measured in 10 mm phosphate buffer containing 2% DMSO. Non-linear fitting of F/F 0 ratios as a function of ginsenosides concentrations was performed to calculate the apparent binding constants. [IA] = 10 µm, [FBA] = 5 µm, λ ex = 421 nm, λ em = 466 nm. F 0 : fluorescence intensity of IA/FBA ensembles, F: fluorescence intensity upon addition of the analytes. S-10

11 a) F/F 0 at 526 nm 2.0 IB/FBA1 IB/FBA2 1.8 IB/FBA3 IB/FBA [Rb1] (mm) b) F/F 0 at 526 nm IB/FBA1 IB/FBA2 IB/FBA3 IB/FBA [Rb3] (mm) c) F/F 0 at 526 nm IB/FBA1 IB/FBA2 IB/FBA3 IB/FBA4 d) F/F 0 at 526 nm IB/FBA1 IB/FBA2 IB/FBA3 IB/FBA [Rd] (mm) [Rg1] (mm) e) F/F 0 at 526 nm 1.7 IB/FBA1 IB/FBA2 1.6 IB/FBA3 1.5 IB/FBA [Re] (mm) Figure S11. Relative fluorescence recovery of IB/FBA ensembles upon addition of a) Rb1, b) Rb3, c) Rd, d) Rg1 and e) Re (7 replicates), measured in 10 mm phosphate buffer containing 2% DMSO. Non-linear fitting of F/F 0 ratios as a function of ginsenosides concentrations was performed to calculate the apparent binding constants. [IB] = 10 µm, [FBA] = 3 µm, λ ex = 408 nm, λ em = 526 nm. F 0 : fluorescence intensity of IB/FBA ensembles, F: fluorescence intensity upon addition of the analytes. S-11

12 Figure S12. Illustration of the process for screening the most important contributors in the array. a) PCA for all eight sensing ensembles showed that the main contributors for ginsenosides discrimination were IA/FBA1, IA/FBA4, IB/FBA3, IB/FBA1 and IB/FBA4. Among them, three sensor elements were chosen from PC1, which carried about the overwhelming majority of the total variance. b) IA/FBA2, IA/FBA3 and IB/FBA2 were excluded from the array, and the remaining elements were analyzed again with PCA. It was found that the main contributors were IB/FBA3, IB/FBA1 and IB/FBA4. c) IA/FBA1 and IA/FBA4 were excluded from the array, and PCA was carried out using the remaining three sensor elements. Although a moderate overlap was observed between the data points of Rb1 and Rb3, the discrimination situation was still acceptable, with 88.3% classification accuracy analyzed by LDA (see Figure S13). S-12

13 Figure S13. a) 2D canonical score plot of five ginsenosides at a concentration range (0.1 2 mm, 7 replicates for each concentration level), analyzed by LDA on the basis of the simplified array with three sensor elements. b) Classification accuracy of 88.3% was obtained via cross-validation. S-13

14 Table S1. The detection limits (mm) of ginsenosides. Rb1 Rb3 Rd Rg1 Re IA-FBA IB-FBA Table S2. List of the apparent binding constants (K b, M -1 ) of ginsenosides using different sensing ensembles. Protopanaxadiols Protopanaxatriols Rb1 Rb3 Rd Rg1 Re IA/FBA IA/FBA IA/FBA IA/FBA IB/FBA IB/FBA IB/FBA IB/FBA Table S3. Abstract of the discrimination functions. Discrimination Proporations of Cumulative Canonical Eigenvalues functions total variance (%) proporations (%) correlations S-14

15 Table S4. Classification results of ginsenoside samples at a concentration range (0.1 2 mm, 7 replicates for each concentration level), analyzed by QDA on the basis of the simplified array with three sensor elements. Classification results (QDA) Group Rb1 Rb3 Rd Rg1 Re Correct Rb % Rb % Rd % Rg % Re % Accuracy: 322/350 (92.0%) The separate-groups covariance matrix was employed to achieve QDA, instead of the within-groups covariance matrix used in LDA. Additionally, in the QDA process, the quadratic curves were used as the boundaries between analytes instead of the linear curves. S-15

16 Table S5. Results of the multi-layered LDA for five ginsenosides at a concentration range (0.1 2 mm, 7 replicates for each concentration level), based on the simplified array with three sensor elements. The insight on inherent features of ginsenoside analytes was incorporated into the discrimination event. a): In the first layer, the titration data for the 70 samples (10 concentrations 7 replicates) of Rb1, Rb3 and Rd were combined as the protopanaxadiols data set including a total of 210 samples. Similarly, 70 samples of Rg1 and Re were combined as the protopanaxatriols sample set with a total of 140 samples. The classification was based on the insight of inherent features of ginsenosides, and the samples belonged to each category were treated as a same analyte. Then LDA was performed with 99.7% accuracy. b) and c): In the second layer, the two categories (i.e. protopanaxadiols and protopanaxatriols) were broken down into individual ginsenosides, respectively. Then two separate LDA processes were performed to discriminate the components of each class. The 70 samples of each ginsenoside were treated as a same analyte regardless of the varying concentrations. Consequently, the discrimination accuracies of protopanaxadiols and protopanaxatriols were calculated to be 87.1% and 98.6%, respectively. S-16

17 Table S6. Data matrix of the relative fluorescence recovery upon addition of analytes at different concentrations into PPE/FAB emsembles (matrix A = ( ) ). No. Tested samples F/F 0 IA/FBA1 IA/FBA2 IA/FBA3 IA/FBA4 IB/FBA1 IB/FBA2 IB/FBA3 IB/FBA4 Constant a 1 Rb1-0.5 mm Rb1-1.0 mm Rb1-1.5 mm Rb3-0.5 mm Rb3-1.0 mm Rb3-1.5 mm Rd-0.5 mm Rd-1.0 mm Rd-1.5 mm Rg1-0.5 mm Rg1-1.0 mm Rg1-1.5 mm Re-0.5 mm Re-1.0 mm Re-1.5 mm a The constant row was added artificially to enable the multiplication operation between matrix A and B or D with a constant line. Table S7. Coefficient matrix of grouping variables (matrix B = ( ) ), obtained from the established mathematical model. Grouping variables Rb1 Rb3 Rd Rg1 Re IA/FBA IA/FBA IA/FBA IA/FBA IB/FBA IB/FBA IB/FBA IB/FBA Constants S-17

18 Table S8. Identification of the tested samples and corresponding score matrix (matrix C = AB = ( ) ). No. Actual samples Scores Results of Idendification Rb1 Rb3 Rd Rg1 Re LDA ( or ) 1 Rb1-0.5 mm Rb3 2 Rb1-1.0 mm Rd 3 Rb1-1.5 mm Rb1 4 Rb3-0.5 mm Rb3 5 Rb3-1.0 mm Rb3 6 Rb3-1.5 mm Rb3 7 Rd-0.5 mm Rd 8 Rd-1.0 mm Rd 9 Rd-1.5 mm Rd 10 Rg1-0.5 mm Rg1 11 Rg1-1.0 mm Rg1 12 Rg1-1.5 mm Rg1 13 Re-0.5 mm Re 14 Re-1.0 mm Re 15 Re-1.5 mm Re For each kind of ginsenoside, three different concentrations (0.5/1.0/1.5 mm) were taken into consideration. These samples were treated as the unknown, the average fluorescence signals of three replicates (towards each concentration level) obtained from the sensor array were collected as a matrix to perform a categorization procedure (Table S6, i.e. matrix A). Based on the preceding mathematical model established via LDA, a coefficient matrix of different analytes was exported (Table S7, i.e. matrix B). Multiplication operation between the two matrices enabled the generation of a score matrix (Table S8, i.e. matrix C). An unknown sample can be identified as the category where the highest score exhibited among all five ginsenosides. S-18

19 Table S9. Non-standardized coefficient matrix of discriminant functions (matrix D = ( ) ), obtained from the established mathematical model. Discriminant functions Factor 1 (X-axis) Factor 2 (Y-axis) Factor 3 (Z-axis) IA/FBA IA/FBA IA/FBA IA/FBA IB/FBA IB/FBA IB/FBA IB/FBA Constants Table S10. Three-dimensional coordinates matrix of the tested samples (matrix E = AD = ( ) ). Calculated coordinates No. of samples Actual samples X-axis Y-axis Z-axis 1 Rb1-0.5 mm Rb1-1.0 mm Rb1-1.5 mm Rb3-0.5 mm Rb3-1.0 mm Rb3-1.5 mm Rd-0.5 mm Rd-1.0 mm Rd-1.5 mm Rg1-0.5 mm Rg1-1.0 mm Rg1-1.5 mm Re-0.5 mm Re-1.0 mm Re-1.5 mm S-19

20 Figure S14. 1 H-NMR of FBA1. Figure S15. 1 H-NMR of FBA2. S-20

21 Figure S C-NMR of FBA2. Figure S17. 1 H-NMR of compound 2. S-21

22 Figure S C-NMR of compound 2. Figure S19. 1 H-NMR of compound 3. S-22

23 Figure S C-NMR of compound 3. Figure S21. 1 H-NMR of FBA3. S-23

24 Figure S C-NMR of FBA3. Figure S23. 1 H-NMR of FBA4. S-24

25 Figure S C-NMR of FBA4. S-25