Detection of three chloropropanols in chicken essence by microemulsion capillary electrokinetic chromatography
A microemulsion electrokinetic chromatographic(MEEKC) method was developed to analyze and detect three chloropropanols [3-monochloropropane-1,2-diol(3-MCPD), 1,3-dichloropropan-2-ol(1,3- DCP) and 2,3-dichloropropan-1-ol(2,3-DCP)] in chicken essence. The effects of sodium dodecyl sulfate(SDS) surfactant, pH and concentration of buffer solution, organic modifier, co-surfactant, temperature and operating voltage were examined in order to optimize the separation. A highly efficient MEEKC separation method was achieved by using a microemulsion solution of pH 9.0 containing 3.31%(w/v) SDS,6.61%(w/v)1-butanol, 0.81%(w/v) octane, 10%(v/v) acetonitrile and 79.3%(v/v) 5 mmol/L phosphateborax buffer solution. The amount of organic modifier(acetonitrile) was determined as apparent influence on the separation resolution. The three chloropropanols were baseline separated within 16 min at 20 kV and 20 ℃. The detection wavelength was 192 nm. Good linear relations(r0.998) between peak areas and concentration of analytes were established in the range of 2.5～500 μg/mL for 3-MCPD, 1.0～500 μg/mL for 1,3-DCP and 2,3-DCP. The detection limits(S/N=3) were 0.5, 0.4, 0.5 μg/mL, respectively. The MEEKC method has been successfully applied for the analysis of three chloropropanols in chicken essence with satisfactory results.