Analysis of aliphatic amines using head-column field-enhanced sample stacking in MEKC with LIF detection
Jianhua Zhang1, Huimin Cui, Liangjun Xu
1Ministry of Education Key Laboratory of Analysis and Detection Technology for Food Safety, Department of Chemistry, Fuzhou University, Fuzhou, Fujian, P. R. China.
Electrophoresis
|January 31, 2009
Summary
This study introduces head-column field-enhanced sample stacking for concentrating aliphatic amines in MEKC. The method significantly improves detection limits for analyzing these compounds in environmental samples.
Area of Science:
- Analytical Chemistry
- Separation Science
- Environmental Analysis
Background:
- Capillary electrophoresis techniques like MEKC are crucial for analyzing complex mixtures.
- Pre-capillary derivatization is often necessary to enhance analyte detectability.
- On-line sample pre-concentration methods are vital for improving sensitivity in trace analysis.
Purpose of the Study:
- To develop and optimize a method for the determination of C1-C9 aliphatic amines using MEKC.
- To implement head-column field-enhanced sample stacking for on-line concentration of derivatized aliphatic amines.
- To validate the method for analyzing aliphatic amines in real-world environmental samples like river water.
Main Methods:
- Pre-capillary derivatization of C1-C9 aliphatic amines with 3-(4-carboxybenzoyl) quinoline-2-carboxaldehyde (CBQCA).
- On-line sample concentration using head-column field-enhanced sample stacking in Microchip Electrophoresis with a Chemical Imprint (MEKC).
- Optimization of derivatization molar ratio, buffer pH, and running buffer composition (sodium borate and SDS).
- Baseline separation of nine imidazole aliphatic amines within 12 minutes.
Main Results:
- Optimized molar ratio of CBQCA to amines at 120:1 and derivatization buffer at 50 mmol/L borate (pH 9.5).
- Achieved baseline separation of nine aliphatic amines using 50 mmol/L sodium borate (pH 9.5) and 15 mmol/L SDS running buffer.
- Detection limits for the nine aliphatic amines ranged from 1.2 to 3.8 pmol/L (S/N=3).
- Demonstrated 49-173-fold improvement in detection limits compared to conventional sample injection.
Conclusions:
- Head-column field-enhanced sample stacking is an effective on-line concentration technique for MEKC analysis of aliphatic amines.
- The developed method provides high sensitivity and efficiency for determining C1-C9 aliphatic amines.
- The method is validated and suitable for the analysis of aliphatic amines in river water samples, showing good recovery rates.
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