TY - JOUR
T1 - Saturated fatty acid determination method using paired ion electrospray ionization mass spectrometry coupled with capillary electrophoresis
AU - Lee, Ji Hyun
AU - Kim, Su Jin
AU - Lee, Sul
AU - Rhee, Jin Kyu
AU - Lee, Soo Young
AU - Na, Yun Cheol
N1 - Funding Information:
This work was supported by the National Research Council of Science and Technology through the Degree & Research Center program ( DRC-14-1-KBSI ). Appendix A
Publisher Copyright:
© 2017 Elsevier B.V.
PY - 2017/9/1
Y1 - 2017/9/1
N2 - A sensitive and selective capillary electrophoresis-mass spectrometry (CE-MS) method for determination of saturated fatty acids (FAs) was developed by using dicationic ion-pairing reagents forming singly charged complexes with anionic FAs. For negative ESI detection, 21 anionic FAs at pH 10 were separated using ammonium formate buffer containing 40% acetonitrile modifier in normal polarity mode in CE by optimizing various parameters. This method showed good separation efficiency, but the sensitivity of the method to short-chain fatty acids was quite low, causing acetic and propionic acids to be undetectable even at 100 mgL−1 in negative ESI-MS detection. Out of the four dicationic ion-pairing reagents tested, N,N’-dibutyl 1,1’-pentylenedipyrrolidium infused through a sheath-liquid ion source during CE separation was the best reagent regarding improved sensitivity and favorably complexed with anionic FAs for detection in positive ion ESI-MS. The monovalent complex showed improved ionization efficiency, providing the limits of detection (LODs) for 15 FAs ranging from 0.13 to 2.88 μg/mL and good linearity (R2 > 0.99) up to 150 μg/mL. Compared to the negative detection results, the effect was remarkable for the detection of short- and medium-chain fatty acids. The optimized CE-paired ion electrospray (PIESI)-MS method was utilized for the determination of FAs in cheese and coffee with simple pretreatment. This method may be extended for sensitive analysis of unsaturated fatty acids.
AB - A sensitive and selective capillary electrophoresis-mass spectrometry (CE-MS) method for determination of saturated fatty acids (FAs) was developed by using dicationic ion-pairing reagents forming singly charged complexes with anionic FAs. For negative ESI detection, 21 anionic FAs at pH 10 were separated using ammonium formate buffer containing 40% acetonitrile modifier in normal polarity mode in CE by optimizing various parameters. This method showed good separation efficiency, but the sensitivity of the method to short-chain fatty acids was quite low, causing acetic and propionic acids to be undetectable even at 100 mgL−1 in negative ESI-MS detection. Out of the four dicationic ion-pairing reagents tested, N,N’-dibutyl 1,1’-pentylenedipyrrolidium infused through a sheath-liquid ion source during CE separation was the best reagent regarding improved sensitivity and favorably complexed with anionic FAs for detection in positive ion ESI-MS. The monovalent complex showed improved ionization efficiency, providing the limits of detection (LODs) for 15 FAs ranging from 0.13 to 2.88 μg/mL and good linearity (R2 > 0.99) up to 150 μg/mL. Compared to the negative detection results, the effect was remarkable for the detection of short- and medium-chain fatty acids. The optimized CE-paired ion electrospray (PIESI)-MS method was utilized for the determination of FAs in cheese and coffee with simple pretreatment. This method may be extended for sensitive analysis of unsaturated fatty acids.
KW - Capillary electrophoresis-mass spectrometry (CE-MS)
KW - Ion paring reagent
KW - Paired ion electrospray ionization (PIESI)
KW - Saturated fatty acid
UR - http://www.scopus.com/inward/record.url?scp=85023172734&partnerID=8YFLogxK
U2 - 10.1016/j.aca.2017.06.052
DO - 10.1016/j.aca.2017.06.052
M3 - Article
C2 - 28843567
AN - SCOPUS:85023172734
SN - 0003-2670
VL - 984
SP - 223
EP - 231
JO - Analytica Chimica Acta
JF - Analytica Chimica Acta
ER -