Analysis of low molecular weight acids by monolithic immobilized pH gradient-based capillary isoelectric focusing coupled with mass spectrometry

✍ Scribed by Tingting Wang; Agnes Fekete; Andras Gaspar; Junfeng Ma; Zhen Liang; Huiming Yuan; Lihua Zhang; Philippe Schmitt-Kopplin; Yukui Zhang

• Publisher: John Wiley and Sons
• Year: 2011
• Tongue: English
• Weight: 199 KB
• Volume: 34
• Category: Article
• ISSN: 1615-9306
• DOI: 10.1002/jssc.201000720

✦ Synopsis

Abstract

A novel method for the separation and detection of low molecular weight (LMW) acids was developed using monolithic immobilized pH gradient‐based capillary isoelectric focusing coupled with mass spectrometry. Two main parameters, focusing conditions and delivery buffer conditions, which might affect separation efficiency, were optimized with the focusing time of 7 min at 350 V/cm and the delivery buffer of 50% (v/v) acetonitrile in 10 mmol/L ammonium formate (pH 3.0). Under these conditions, the linear correlation between the volume of delivery solvent and the p__K__~a~ of the model components was observed. In addition, the separation mechanism of LMW acids was proposed as well. We suppose that this method may provide a useful tool for the characterization of LMW components (e.g. natural organic matter of different origins).