Simultaneous Determination of Four Sudan Dyes in Egg Yolks by Molecularly Imprinted SPE Coupled with LC-UV Detection

Abstract

A highly selective molecularly imprinted solidphase extraction (MISPE) combined with liquid chromatography-ultraviolet detection was developed for the simultaneous isolation and determination of four Sudan dyes (I, II, III and IV) in egg-yolk products. The imprinted microspheres synthesized by suspension polymerization using phenylamine-naphthol as mimic template show high selectivity and affinity to the four kinds of Sudan dyes and were successfully applied as selective sorbents of solidphase extraction for the simultaneous determination of the four Sudans from egg-yolk samples. Good linearity was obtained in a range of 0.062-10 lg g -1 and the average recoveries of the four Sudans at three spiked levels ranged from 94.1 to 102.5% with the relative standard deviations less than 5.8%. The developed extraction protocol eliminated the effect of template leakage on quantitative analysis and could be applied for the determination of Sudans in complicated food samples.

Determination of illegal dyes in eggs by liquid chromatography - tandem mass spectrometry

“…Due to this fact, additional elution with 0.1% formic acid in acetonitrile had to be applied. The recoveries, which were between 97%-105%, are comparable with those obtained by Qiao J. et al (16), Yu C. et al (24), and Zhixiang X et al (25). It demonstrates the suitability of the zirconium coated silica material for the analysis of illegal dye residues, but the matrix effect was not minimised as much as it was expected.…”

“…The ELISA-based methods for the fast screen of their presence (1,3,14,18) as well as innovatory method based on computer image analysis technique, which allow to distinguish naturally dyed eggs from eggs artificially dyed with Sudan dyes without any previous preparation for the analysis, were also developed (26). However, the most common are liquid chromatography methods with different types of detectors, mainly diode-array (12,21) or spectrophotometric detector (9,16,23). Recently, tandem mass spectrometry seems to be the most suitable for multiresidue analysis because of its sensitivity and selectivity (4,10,15).…”

“…The methods published so far utilise HPLC C 18 columns (9,12,15). The dyes are extracted using acetonitrile (16,25) or acetone (9) and cleaned using different SPE columns (10,21,25). This paper presents the development and validation of a method for the simultaneous determination of 10 illegal dyes in egg yolks using liquid chromatography -tandem mass spectrometry and clean-up with zirconium coated silica SPE cartridge and HPLC C 18 column.…”

Molecularly imprinted microspheres as SPE sorbent for selective extraction of four Sudan dyes in catsup products

“…However, this method suffers from the waste of organic solvents, is time-consuming and has potential toxicity hazards [13]. Other sample preparation methods, such as solid-phase extraction (SPE) [14,15], liquid phase microextraction [16], matrix solidphase dispersion [17], dual solvent-stir bars microextraction [14], ultrasonic-assisted extraction [18] and centrifugal sedimentation [19,20] are also reported for Sudan dyes analysis. However, the selectivity of these pretreatment procedures needs to be further improved.…”

Rapid and selective screening of melamine in bovine milk using molecularly imprinted matrix solid-phase dispersion coupled with liquid chromatography-ultraviolet detection

“…Molecular imprinting is a rapidly developing technique for the preparation of polymers having specific molecular recognition properties for a given compound, its analogs or for a single enantiomer [27][28][29]. As the artificial polymers, MIPs are easy and rapid to prepare, very stable in harsh conditions and allow the usage of a great variety of binding/eluting conditions without the risk of losing binding activity.…”