Amperometric Determination of Ascorbic Acid in Real Samples Using a Disposable Screen-Printed Electrode Modified with Electrografted o-Aminophenol Film

作者：Civit Laia; Nassef Hossam M; Fragoso Alex^*; O'Sullivan Ciara K

来源：Journal of Agricultural and Food Chemistry, 2008, 56(22): 10452-10455.

DOI：10.1021/jf802536k

• Amperometric sensor
• ascorbic acid
• electrocatalytic oxidation
• diazonium salt
• modified electrode
• screen-printed electrodes
• fruits
• vegetables
• commercial juices

Ascorbic acid (AA) is an antioxidant considered to play a crucial role in human health. Therefore, diverse methods for the determination of AA in foods have been developed, most of them time-consuming and requiring costly instrumentation. A simple and sensitive method for the quantification of AA in fresh fruits and vegetables and commercial juices using an amperometric sensor is presented on the basis of disposable screen-printed carbon electrodes (SPEs) modified with an o-aminophenol (o-AP) film selective for the detection of AA. The sensor exhibited a linear response for AA from 2-20 mu M, with a correlation coefficient r(2) = 0.998 and a limit of detection of 0.86 mu M. Common possible interferents of the sample matrices were tested, and results showed high selectivity of the o-AP SPEs toward AA. The sensor exhibited an excellent reproducibility (RSD% = 1.98, n = 8) and surface stability. The method was validated by a comparison to a reference method, and excellent correlation is obtained.

• 出版日期2008-11-26