1. Supplementary information to manuscript:
Determination of benzotriazoles in water samples by concurrent derivatization-dispersive liquid-liquid microextraction followed by gas chromatography mass spectrometry
J. Casadoa, R. Nescatellib, I. Rodrígueza, M. Ramila*, F. Marinib, R. Celaa
aDepartment of Analytical Chemistry, Nutrition and Food Sciences, IIAA-Institute for Food Analysis and Research, University of Santiago de Compostela, R/Constantino Candeira SN, Santiago de Compostela, Spain.
bDepartment of Chemistry, University of Rome “La Sapienza”. P.le Aldo Moro 5. Rome 00185, Italy

2. 4
x10
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0.6
0.8 1
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1.6
1.8 2
+EI EIC( ) Scan muestreo.D Smooth
Counts vs. Acquisition Time (min)
11.2
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11.9
12.0
12.1
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12.3
12.4
5-ClBTri
Peak 2 2
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1.1
Counts (%) vs. Mass-to-Charge (m/z) 60 80
100
120
140
160
180
200
220
240
260
C8H6N3ClO+
M exp:
M cal:
Error: -0.1 mDa
C8H6NClO+
M exp:
M cal:
C6H4N3Cl+
M exp:
M cal:
Error: 0.4 mDa
C6H4NCl+
M exp:
M cal:
Error: -0.6 mDa
C7H6N+
M exp:
M cal:
Error: 0.7 mDa
C6H4N+
M exp:
M cal:
Error: 0.8 mDa
Peak 1
C8H6N3ClO+
M exp:
M cal:
Error: -0.4 mDa 2
x10
-0.1
0.1
0.2
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0.8
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1.1
Counts (%) vs. Mass-to-Charge (m/z) 60 80
100
120
140
160
180
200
220
240
260
C8H6NClO+
M exp:
M cal:
Error: -0.1 mDa
C6H4N3Cl+
M exp:
M cal:
Error: 0.4 mDa
C6H4NCl+
M exp:
M cal:
Error: -0.3 mDa
C7H6N+
M exp:
M cal:
Error: 1.4 mDa
C6H4N+
M exp:
M cal:
Error: 1.3 mDa
Fig. S1. GC-QTOF-MS chromatogram of an acetylated standard solution of 5-chlorobenzotriazole (1000 ng mL-1) and accurate mass spectra of the two acetylated isomeric products.

3. Table S1. Experimental domain and responses for benzotriazole compounds in the Box-Behnken experimental factorial design.

4. Fig. S2. Comparison of responses (peak areas) between concurrent acetylation-DLLME
(single-step approach) and acetylation followed by DLLME (two-step), n= 3 replicates.
Error bars represent standard deviations.

5. Table S2. Linearity parameters using spiked aliquots (n= 7 levels, 0
Table S2. Linearity parameters using spiked aliquots (n= 7 levels, 0.05 to 20 ng mL-1 ) of different water samples and normalized slope ratios.