Development of a liquid-junction/low-flow interface for phosphate buffer capillary electrophoresis mass spectrometry.
To alleviate ion suppression from phosphate buffer and to preserve separation integrity, a new capillary electrophoresis mass spectrometry (CE-MS) interface was developed. The interface consisted of a low-flow interface and a liquid junction. In this design, both the inlet reservoir and the liquid-junction reservoir were filled with phosphate running buffer. Because the phosphate anions in the column migrated toward the inlet reservoir (away from the electrospray ionization (ESI) source) the problem of ion suppression in ESI was avoided. The liquid junction was incorporated to eliminate issues of degraded separation observed when sheath liquid interfaces use different buffers for separation and MS analysis attributed to differences in anion velocity. The utility of the interface was demonstrated by the analysis of antihistamines at pH 3.5 and the analysis of perfluorocarboxylic acid at pH 9.5.
Li
Fu-An
FA
Department of Chemistry, National Taiwan University, Taipei, Taiwan.
Huang
Ju-Li
JL
Shen
Shang-Yu
SY
Wang
Che-Wei
CW
Her
Guor-Rong
GR
D002021:Buffers; D002264:Carboxylic Acids / Q000032:analysis / Q000737:chemistry; D019075:Electrophoresis, Capillary / Q000295:instrumentation*; D004867:Equipment Design; D006633:Histamine Antagonists / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D013058:Mass Spectrometry / Q000295:instrumentation*; D010710:Phosphates / Q000737:chemistry*
D002021:Buffers; D002264:Carboxylic Acids; D006633:Histamine Antagonists; D010710:Phosphates