Ultra-sensitive quantification of lysozyme based on element chelate labeling and capillary electrophoresis-inductively coupled plasma mass spectrometry

Anal Chim Acta. 2014 Feb 17;812:12-7. doi: 10.1016/j.aca.2014.01.003. Epub 2014 Jan 10.

Abstract

In this study, an ultra-sensitive method for the quantification of lysozyme based on the Gd(3+) diethylenetriamine-N,N,N',N″,N″-pentaacetic acid labeling and capillary electrophoresis-inductively coupled plasma mass spectrometry (CE-ICP-MS) was described. The Gd(3+)-tagged lysozyme was effectively separated by capillary electrophoresis (CE) and sensitively determined by inductively coupled plasma mass spectrometry (ICP-MS). Based on the gadolinium-tagging and CE-ICP-MS, the lysozyme was determined within 12 min with an extremely low detection limit of 3.89 attomole (3.89×10(-11) mol L(-1) for 100 nL of sample injection) and a RSD<6% (n=5). The proposed method has been successfully used to detect lysozyme in saliva samples with a recovery of 91-106%, suggesting that our method is sensitive and reliable. The success of the present method provides a new potential for the biological assays and sensitive detection of low-abundant proteins.

Keywords: Capillary electrophoresis; Inductively coupled plasma mass spectrometry; Lysozyme; Protein; Saliva.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chelating Agents / chemistry*
  • Electrophoresis, Capillary / methods*
  • Gadolinium / chemistry
  • Limit of Detection
  • Mass Spectrometry / methods*
  • Muramidase / analysis*

Substances

  • Chelating Agents
  • Gadolinium
  • Muramidase