Off-Line Concentration of Bisphenol A and Three Alkylphenols by SPE then On-Line Concentration and Rapid Separation by Reverse-Migration Micellar Electrokinetic Chromatography

Abstract

A method for separation of four environmentally important compounds (three alkylphenols and bisphenol A) by cyclodextrin-modified reverse-migration micellar electrokinetic chromatography (CD-RM-MEKC) has been optimized. On-line concentration, stacking using reversemigrating micelles and a water plug (SRW), was used to improve the limit of detection. Two main factors affecting the efficiency of enhancement by SRW, injection sample length and water-plug length, are discussed in detail. Compared with the normal 2-s injection, more than 121-fold enhancement of peak area and more than 71-fold enhancement of peak height were achieved with 120-s sample injection after 120-s water-plug injection. With this optimized separation method and SRW technology, limits of detection were found to be 0.089, 0.030, 0.0091, and 0.033 mg L )1 for 4-nonylphenol, 4-tert-octylphenol, bisphenol A, and 4-tertbutylphenol, respectively. Calibration plots (R 2 ‡ 0.9968) and relative standard deviations (RSD, %) of corrected peak areas and migration time were also satisfactory. Combined with offline concentration by solid-phase extraction (SPE) this method might be used to determine these contaminants at ppb levels in groundwater samples.

MEKC: An update focusing on practical aspects

“…There have been several reports on the use of sample stacking in MEKC over the period covered in this review. In most cases, the normal stacking mode with SDS was used to improve the sensitivity in the determination of various analytes, such as Viagra and its metabolite [47], plant hormones [48], morphine [49], and ecdysteroids [50]; however, other stacking modes have also been employed such as stacking with reverse migration of micelles [51][52][53] and high-salt sample stacking [54] in addition to new approaches such as so-called "ACN stacking" (viz the addition of ACN and salts to the sample matrix in order to narrow analyte bands) [55] and the "orthogonal analyte stacking/injection system" proposed by Palmer et al [56].…”

Highly sensitive determination of tetrabromobisphenol A and bisphenol A in environmental water samples by solid‐phase extraction and liquid chromatography‐tandem mass spectrometry

“…Correlation coefficients (R) ranged from 0.9985 to 0.9998. Compared with previous SPE-HPLC-UV, SPE-MEKC and SPE-LVSEP-NACE methods, the proposed SPE-RRLC-MS/MS method can achieve much lower LODs [17][18][19]. These experimental results proved that the present method was very sensitive and useful in the trace analysis of TBBPA and BPA in water samples.…”

In Situ Determination of Bisphenol A in Beverage Using a Molybdenum Selenide/Reduced Graphene Oxide Nanoparticle Composite Modified Glassy Carbon Electrode

“…To monitor the environmental levels, behaviors and fate of BPA, many methods, such as capillary electrophoresis [ 11 ], gas chromatography coupled with mass spectrometry (GC-MS) [ 12 ], high performance liquid chromatography mass spectrometry (HPLC-MS) [ 13 ], enzyme linked immune sorbent assay (ELISA) [ 14 ], electrochemical methods [ 15 , 16 ], etc., have been developed. Combined with pretreatment procedures of solid-phase extraction [ 17 ], liquid-liquid extraction [ 18 ] and immunoaffinity chromatography [ 19 ], GC-MS, HPLC-MS and ELISA can be used for selectively and sensitively determining BPA in complex matrices [ 20 , 21 ]. However, the complementary pretreatments and expensive equipment have restricted their application.…”