Electronic Supplementary Material (ESI) for Journal of Analytical Atomic Spectrometry
This journal is © The Royal Society of Chemistry 2011
Methodological artefacts in the XANES analysis of hexacoordinated
pentavalent arsenic
Iris Koch,a Maeve Moriartya Jie Suia and Kenneth J. Reimer*a
† Environmental Sciences Group, Royal Military College of Canada, Kingston, Ontario, K7K
7B4, Canada
The electronic supplementary information includes a description of the mass spectrometric
experiment with the As(V)-glycerol compound, along with the results, and the XANES spectra
obtained during the pH stability experiment of the As(V)-glycerol experiment.
Mass Spectrometric Analysis
The As(V)-glycerol compound was dissolved in acetonitrile (12 mg in 2.4 mL to obtain
~5mg/mL) and directly infused to a Waters Micromass ZQ mass spectrometer, capable of
electrospray (ESI) or atmospheric pressure chemical ionization (APCI). The compound was
analyzed in ESI negative mode using the following parameters: capillary voltage 3.00 kV, cone
voltage -55.56 V, extractor voltage -4.03 V, source temperature 100°C, desolvation temperature
200°C, desolvation flow rate 250 L/h, cone flow rate 66 L/h. A mass spectrum in ESI positive
mode was also obtained with the following parameters: capillary voltage 3.00 kV, cone voltage
36.00 V, extractor voltage 3.00 V, source temperature 90°C, desolvation temperature 250°C,
desolvation flow rate 250 L/h, cone flow rate 59 L/h.
Negative ions ([M]-) were observed in ESI negative mode (Figures S1a and S1b) that
corresponded to the molecular mass of As(V)-glycerol (75 for As + 3  90.33 for glycerol - 1 =
m/z 345). Figure S2 shows the observed molecular ion [M]- was in good agreement with the
theoretical mass distribution generated by MassLynx software.
The results from positive ESI are shown in Figure S3, with peaks at m/z 115.5, m/z 207.5
and m/z 279.6 corresponding to [glycerol+Na]+, [2glycerol+Na]+ and [3glycerol-3HO2+K]+
respectively. In the spectrum, a series of unknown polymer pattern peaks with a repeat unit of
85 were also observed.
Also included are:
Figure S1
Figure S2
Figure S3
Figure S4
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Electronic Supplementary Material (ESI) for Journal of Analytical Atomic Spectrometry
This journal is © The Royal Society of Chemistry 2011
neg mode
neg mode
AS COMPOUND 3 1 (2.003)
AS COMPOUND 3 1 (2.003)
146.8
100
Scan ES1.03e8
345.1
100
Scan ES1.10e9
OH
OH
1a
1b
O
O
-
As
O
O
O
%
O
%
OH
346.0
338.0
0
m/z
326 328 330 332 334 336 338 340 342 344 346 348 350 352 354 356 358 360 362 364 366 368 370 372 374 376 378 380 382 384 386
430.0
Zoom in
231.9
124.8
345.1
713.0
401.9
0
m/z
100
125
150
175
200
225
250
275
300
325
350
375
400
425
450
475
500
525
550
575
600
625
650
675
700
725
750
775
Figure S1a and 1b (inset). Negative ESI of As(V)-glycerol compound, with [M]- peak at m/z 345.
2
Electronic Supplementary Material (ESI) for Journal of Analytical Atomic Spectrometry
This journal is © The Royal Society of Chemistry 2011
neg mode
AS COMPOUND 3 (2.003) Cu (0.30); Is (1.00,1.00) C9H18AsO9
Scan ES8.84e12
345.0
100
%
2a. Theoretical spectrum
346.0
0
AS COMPOUND 3 1 (2.003)
Scan ES1.03e8
OH
345.1
100
2b Actual spectrum
OH
O
O
-
As
O
O
O
%
O
346.0
OH
338.0
0
m/z
324 326 328 330 332 334 336 338 340 342 344 346 348 350 352 354 356 358 360 362 364 366 368 370 372 374 376 378 380 382
Figure S2a and 2b. Negative ESI mass spectrum of As(V) glycerol compound compared with theoretical ESI mass spectrum
generated by MassLynx software.
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Electronic Supplementary Material (ESI) for Journal of Analytical Atomic Spectrometry
This journal is © The Royal Society of Chemistry 2011
positive mode
AS COMPOUND 1 1 (1.300)
115.5
100
Scan ES+
6.72e8
[glycerol + Na]+
[2glycerol + Na]+
%
207.5
108.3
[3glycerol-2H2O + K]+
279.6
193.4
156.5
278.5
Polymers with repeat unit ~85
363.6
171.5
251.5
149.4
533.5
+85
234.5
61.6
448.5
+85
+85
+85
788.4
703.4
618.5
+85
+85
873.3
+85
+85
958.3
0
50
100
150
200
250
300
350
400
450
500
550
600
650
700
750
800
850
900
950
m/z
1000
Figure S3. Positive ESI mass spectrum of As(V) glycerol compound.
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Electronic Supplementary Material (ESI) for Journal of Analytical Atomic Spectrometry
This journal is © The Royal Society of Chemistry 2011
pH 12
pH 9
pH 6
pH 4
pH 1
As(V)
11860
11865
11870
11875
11880
11885
11890
11895
11900
Figure S4. XANES spectra of As(V)-glycerol compound analyzed at different pHs.
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