Supporting Information for

A Simple Microdroplet Chip Consisting of Silica Nanochannel-Assisted Electrode and

Paper Cover for Highly Sensitive Electrochemiluminescent Detection of Drugs in

Human Serum

Yi Xiao‡, Linru Xu‡, Ping Li, Xiao-Chong Tang, Lian-Wen Qi*

State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing

210009, Jiangsu, China

*Correspondence: Tel: +86 25 86185559; Fax: +86 25 83271379; Email address:

Qilw@cpu.edu.cn.

Table of Content

S1. TEM and cross-sectional SEM images of the SNC film

S2. Electrochemical characterization of SNC/ITO electrode

S3. Analytical results for drugs on bare ITO chip in buffers (n=3a)

S4. Comparison of different methods for drug detection

S5. ECL images and calibration curves for drug detection in human serum

S6. Analytical results for drugs on bare ITO chip in human serum (n=3a)

S7. Specificity of the SNC&P-chip

S8. HPLC-UV method for drug detection

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S1. TEM and cross-sectional SEM images of the SNC film

Figure S1. (A) TEM and (B) cross-sectional SEM images of the SNC film.

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S2. Electrochemical characterization of SNC/ITO electrode

Figure S2. CVs obtained at the bare ITO (black), CTAB/SNC/ITO (red), and SNC/ITO electrodes (green) in 0.05 M KHP solution containing 30 M (A) K3[Fe(CN)]6, (B)

Ru(NH3)6Cl3, and (C) FcMeOH. The scan rate was 50 mV s-1.

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S3. Analytical results for drugs on bare ITO chip in buffers (n=3a)

Table S1. Analytical results for drugs on bare ITO chip in buffers (n=3a)

Drugs Fitting equationDynamic range

(M)LOD (nM)

R

matrine Y=1463.3+22.3X 0.150 233 0.9967

metoprololY

=1049.5+0.9813X0.1100 8826 0.9634

chlorphenamine

Y=1060.0+26.0X 0.1100 199.8 0.9799

lincomycin Y=1024.4+13.5X 0.1100 898.0 0.9905levosulpiride Y=1052.7+101.7X 0.125 61.42 0.9944sophoridine Y=1340.3+72.7X 0.140 63.05 0.9987

sophocarpine Y=1710.0+29.9X 0.150 115.9 0.9940a Average of three determinations.

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S4. Comparison of different methods for drug detection

Table S2 Comparison of analytical performance of the proposed SNC&P-chip with other sensors

Analyte Method Dynamic range LOD Ref.

Matrine Ru-AuNPs/MWCNTs-NAF/GCE 2.0 1066.0 103 M 0.7 M [1]

L-cysteine/GO-CS/GCE 4.0 1061.0 104 M 2 M [2]

Ru/mSiO2/NAF/GCE 1.5 10−62.0 10−3 M 0.5 M [3]the SNC&P-chip 0.150 M 4.021 nM This work

Metoprolol MIP/MWCNTs/PGE 0.06490 M 2.88 nM [4]

NAF/CNT/GCE 7.02 1089.0 106 M 3.51 108 M [5]BDD electrode 0.3822 M 0.034 M [6]the SNC&P-chip 0.1100 M 11.43 nM This work

Chlorphen -amine NAF/TiO2/GCE 2 108 106 g/mL 6 109 g/mL [7]

the SNC&P-chip 0.1100 M 9.051 nM This work

Lincomycin FI-CL 1 1085 106 g/mL3.5 109 g/mL [8]

LC-EC up to 1 mM 0.08 M [9]

MWNTs/DHP/GCE 4.5 101.5 10 M 2.0 107 M [10]the SNC&P-chip 0.1100 M 4.009 nM This work

Levosulpiride CE-ECL 1.0 1071.0 104 M 1.0 108 M [11]

the SNC&P-chip 0.125 M 3.042 nM This work

Sophoridine NAF/PTC-NH2/Ru/Pt 2.5 1082.0 106 M 5.0 109 M [12]the SNC&P-chip 0.140 M 1.8 nM This work

Sophocarpine HPLC-ECL 2.0 1096.0 105 M 1 1010 g/mL [13]the SNC&P-chip 0.150 M 2.703 nM This work

Ru-AuNPs, Ru(bpy)32+/nano-Au nano-sphere; MWCNTs, multi-wall carbon nanotubes; NAF, nafion;

GCE, glassy carbon electrode; GO, graphene oxide; CS, chitosan; MIP, molecularly imprinted polymer;

PGE, pencil graphite electrode; CNT, carbon nanotube; BDD, boron-doped diamond electrode; TiO2,

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nano-titania; FI-CL, flow-injection chemiluminescence; LC-EC, liquid chromatography-

electrochemistry; DHP, dihexadecylphosphate; CE-ECL, capillary electrophoresis-

electrochemiluminescence; PTC, 3,4,9,10-perylenetetracarboxylic dianhydride; Pt, Pt disk electrode.

HPLC-ECL, high-performance liquid chromatography-electrochemiluminescence.

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S5. ECL images and calibration curves for drug detection in human

serum

Figure S3 (A) ECL images and (B) calibration curves for six drugs on bare ITO chip and SNC&P-chip in human serum containing Ru(bpy)32+. Points 1 to 6 correspond

to the concentrations of drugs ranking from low to high.

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S6. Analytical results for drugs on bare ITO chip in human serum (n=3a)

Table S3 Analytical results for drugs on bare ITO chip in human serum (n=3a)

Drugs dded (M) Found (M) Recovery (%) RSD (%)

matrine 20 20.478 102.39 3.6

metoprolol 50 190.226 380.45 38

chlorphenamin

e50 58.908 117.82 5.4

lincomycin 80 86.944 108.68 2

levosulpiride 20 20.409 102.04 0.6

sophoridine 30 29.543 98.48 5.4

sophocarpine 40 36.829 92.07 4.8a Average of six determinations.

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S7. Specificity of the SNC&P-chip

Figure S4 ECL intensity for 39 drugs on bare ITO chip and SNC&P-chip in PBS containing Ru(bpy)32+. The concentration of drugs are as follows: chlorphenamine (100 M), matrine (50 M), metoprolol (50 M), sophoridine (40 M), sophocarpine

(50 M), levosulpiride (25 M), lincomycin (100 M), clindamycin (100 M), atropine (100 M), lidocaine (100 M), raceanisodamine (100 M), cytisine (100 M), atenolol

(100 M), L-proline (100 M), and scopolamine (100 M), ranitidine (1000 M), gentamycin (1000 M), diphenhydramine (1000 M), ephedrine (1000 M), cefoperazone (1000 M), levetiracetam (1000 M), epinephrine (1000 M),

dopamine (1000 M), amitriptyline (1000 M), tetracaine (1000 M), procaine (1000 M), ammothamnine (1000 M), brucine (1000 M), 5-fluorouracil (1000 M),

quinidine (1000 M), promethazine (1000 M), fluconazole (1000 M), chloramphenicol (1000 M), linezolid (1000 M), trigonelline (1000 M), and

theophylline (1000 M).

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S8. HPLC-UV method for drug detection

Table S4 Analytical results for drugs on HPLC-UV in human serum.

Drugs Fitting equation Dynamic range (M)LOD (M)

LOQ (M)

R

matrine Y=18426+1269.32X 1500 2.975 8.053 0.9997metoprolol Y=-15693.8+689.829X 202000 14.603 20 0.9959

chlorphenamine Y=-1240.7+4682.2X 11000 0.2703 1 0.9999lincomycin Y=12665.75+915.65X 27540 6.772 27 0.9972

levosulpiride Y=-3382.56+2232.03X 88000 2.05 8 0.9982sophoridine Y=133512+1123.27X 808000 40.264 80 0.9999

sophocarpine Y=10664.1+1777.84X 303000 9.336 30 0.9985

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