Determination of Maleic Hydrazide in Potato Samples Using Capillary Electrophoresis with Dual Detection (UV‐Electrochemical)

Abstract

A new method for the separation of a mixture of different herbicides (propham, chlorpropham, asulam, metamitron, linuron, and maleic hydrazide) using MEKC is proposed. A base-line separation for the mixture of herbicides is achieved in less than six minutes. The detection limits obtained for all the herbicides were lower than 1.0 mM using UV detection. This separation method was used for the determination of maleic hydrazide in potato samples. If a dual (UV-electrochemical) detection system is employed, chlorpropham can be also detected. The results obtained showed that electrochemical detection was ten folds more sensitive than UV detection for maleic hydrazide. The detection limit of the proposed method for maleic hydrazide employing electrochemical detection was 1.3 mg g À1, this value is lower than 50 mg g À1 , which is the maximum residue level permitted for this plant growth regulator in potato samples. The results obtained in the work clearly demonstrate the advantage of using electrochemical detection coupled to capillary electrophoresis, using this detection the concentration limits are not compromised by miniaturization and the components required are simple and inexpensive.

Interfacing commercially available capillary electrophoresis to sample preparation and/or detection systems to solve analytical problems

“…No modification was done to adapt the electrochemical cell on the original design of the capillary electrophoresis injection module. Various methodologies, using this interface, for coupling amperometric detection and commercial CE were applied to determination of polyphenols in white wine (Moreno et al 2011), macrocyclic lactone mycotoxins in maize (Sanchez et al 2009) and maleic hydrazide in potatoes (Chicharro et al 2008 …”

Some important combinations of detection techniques for electrophoresis in capillaries and on chips with emphasis on electrochemical principles

“…Asulam, benzthiazuron and symazine were determined in a real matrix of river water. Reference [39] describes the determination of the herbicides propham, chlorpropham, asulam, metamitron, linuron and maleic hydrazide. Maleic hydrazide was determined in a potato extract (the substance is used to suppress sprouting of potatoes stored).…”

“…Dual AMP/UV detection was employed in a series of works [37][38][39] in determinations of various pesticides in artificial and natural samples by micellar electrokinetic capillary chromatography (MEKC). A standard on-capillary UV photometric detector (a component of commercial electrophoretic instrument) was supplemented with an endcapillary amperometric detector in wall-jet configuration.…”

Food analysis: A continuous challenge for miniaturized separation techniques

“…In the period covered by the present review concerning capillary electromigration applications (January 2007 to April 2009), CE has been widely applied to the determination of different harmful analytes (concerning human health) in different food matrices, i.e . pesticides 21–30, antibiotics 31–38, acrylamide 39, 40 and damaging amines 41–43. Furthermore, some other interesting applications have been found in this field, for example, the determination of banned susan azo‐dyes 44, ochratoxin A 45, a good number of adulterants 46, patulin 47 and melamine 48.…”

“…Pesticides are an important matter of concern in food analysis (food safety) in which recent applications of CE can also be found 21–30. In this sense, Carabias‐Martínez et al .…”