Electronic Supplementary Material

Optical choline sensor based on a water-soluble fluorescent conjugated polymer and an enzyme-coupled assay

Yanan Li#a, Hui Huang#a,b, Fanping Shia, Yan Lia, Xingguang Sua*

aCollege of Chemistry, Jilin University, Changchun, 130012, China

bCollege of Biological and Agricultural Engineering, Jilin University, Changchun, 130025, China

*Corresponding author: Tel.: +86-431-5168352, E-mail address:

#These two authors contributed equally to this work.

Fig. S1 The normalized PL intensity of enzyme-coupled biosensor in the present of 10 μmol L-1 choline with different incubation time: (a) 1.0 μmol L-1 PPESO3 in the presence of 250 U L-1 ChOx, 5 μg mL-1 HRP and 20 μmol L-1 catechol; (b-k) represents the addition of 10 μmol L-1 choline to (a) with the incubation time: 0, 5, 10, 15, 20, 25, 30, 40, 50, 60 min, respectively.


Fig. S2 Effect of pH on the PL intensity ratio of enzyme-coupled biosensor. I0 and I are the fluorescence intensity of system in the absence and presence of the 10 μmol L-1 choline, respectively.

Fig. S3 Effect of temperature on the PL intensity ratio of enzyme-coupled biosensor in the present of 10 μmol L-1 choline. I0 and I are the fluorescence intensity of system in the absence and presence of the choline, respectively.


Table S1 Comparison of different methods for determination of choline.

Methods / System / Linear range
(mol L-1) / LOD
(mol L-1) / Ref.
Electrochemistry / ChOx-PDDA-PB-FePO4/GC electrode / 2.0×10-6 - 3.2×10-3 / 4×10-7 / [1]
Electrochemistry / MnO2/PDDA/ChOx/Screen printed electrode (SPE) / 1.3×10-7 - 1.0×10-4 / 1.3×10-7 / [2]
Electrochemistry / ChOx/MWCNTs-GNp/PDDA / 1.0×10-6 - 5.0×10-4 / 3.0×10-7 / [3]
Electrochemistry / HRP-Os/AChE-choline and PB/AChE-choline electrode / 2.0×10-6 - 2.0×10-3
1.0×10-5 - 2.0×10-3 / 1.0×10-7 / [4]
Electrochemistry / HRP/CNT/GC electrode / 5.0×10-5 - 5.0×10-3 / 1.0×10-5 / [5]
Electrochemistry / ChOx/MWCNT/Pt / 5.0×10-6 - 1.0×10-4 / 1.0×10-7 / [6]
Electrochemistry / PB/(EACC/ChOx)10/Pt electrode / 5.0×10-7 - 1.0×10-4 / 5.0×10-7 / [7]
Electrochemistry / ChOX/HRP/SPE / 5.0×10-7 - 7.0×10-5 / 1.0×10-7 / [8]
Fluorometry / H2O2-sensitive QDs / 1.0×10-7 - 9.0×10-7
5.0×10-6 - 1.5×10-4 / 1.0×10-7 / [9]
Fluorometry / PPE/ChOx/HRP/catechol / 1.0×10-7 - 2.0×10-5 / 5.0×10-8 / This work

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