Analysis of Specific Perfluorohexane Sulfonate Isomers by Liquid Chromatography-Tandem Mass Spectrometry: Method Development and Application in Source Apportionment

Table 2

Identification of PFHxS isomers based on the observed specific series of product ions produced from the molecular anion m/z 399.

Fragment ion series

Main product ions (m/z) observed

Series

Formula^a

Possible product ions (m/z)

A1b

A2

M2

A3

M3

A4

A5

M1b

M4

9-Series

[CnF2n+1]^−

69, 119, 169, 219, 269, 319

169, 319

169

169

219

319

319 [219, 269]c

219 [119, 169]^c

0-Series

[CnF2nSO3]^−

80, 130, 180, 230, 280, 330, 380

80

230

230

130, 80

180

1-Series

[CnF2n−1 SO3]^−

111, 161, 211, 261

211

261

161

7-Series

[CnF2n−1O]^−

47, 97, 147, 197

147

197

PFHxS isomer

n-

iso-

2m-

3m-

1m-

1, 1m-

3, 3m-

^a: n = 1, 2, …, 6. ^b: Identified by comparison with the commercially available n-PFHxS standard and its quantitative ion was m/z 80. ^c: Fragment ions that cannot be produced due to the position of the branched chain. : The specific product ions were chosen to quantify the corresponding isomers.