Analytical Assessment of a Home Made Capillary Electrophoresis Equipment with Linear Charge Coupled Device for Visible Light Absorption Detection in the Determination of Food Dyes

Abstract

The performance of modular home made capillary electrophoresis equipment with spectrophotometric detection, at a visible region by means of a miniaturized linear charge coupled device, was evaluated for the determination of four food dyes. This system presents a simple but efficient home made cell detection scheme. A computer program that converts the spectral data after each run into the electropherograms was developed to evaluate the analytical parameters. The dyes selected for analytical evaluation of the system were Brilliant Blue FCF, Fast Green FCF, Sunset Yellow FCF, and Amaranth. Separation was carried out in a 29 cm length and 75 µm I.D fused silica capillary, using 10 mmol L⁻¹ borate buffer at pH 9, with separation voltage of 7.5 kV. The detection limits for the dyes were between 0.3 and 1.5 mg L⁻¹ and the method presented adequate linearity over the ranges studied, with correlation coefficients greater than 0.99. The method was applied for determination and quantification of these dyes in fruit juices and candies.

Keywords:

• Capillary electrophoresis
• Food dyes
• Instrumentation
• Miniaturization
• Spectrophotometric detection

ACKNOWLEDGMENTS

The authors would like to thank the financial support from FAPESP (Fundação de Amparo à Pesquisa do Estado de São Paulo) and CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico), and Professor Marina F. M. Tavares for donnation of the dyes.

Manuscript 6438

Notes

∗Mean of three determinations.

∗Mean of four determinations.

∗∗not present in this matrix.