Design and application of sensitive and selective electrochemical sensors for the determination of biologically important substances have gained considerable interest in recent years [1][2][3][4][5]. Dopamine (DA) is an important neurotransmitter molecule of catecholamines that is widely distributed in the mammalian central nervous system for message transfer. It plays a very important role in the function of central nervous, renal, hormonal, and cardio vascular systems [6]. Extreme abnormalities of DA levels can lead to brain disorders such as parkinsonism and schizophrenia [7,8]. Therefore, developing simple and rapid methods for the sensitive determination of DA in routine analysis is always a challenge [9,10]. In this context, electrochemical techniques have generated considerable attention, in recent years as good tools for the study of electrochemical mechanisms and for the detection and quantification of biological substances, in particular DA, AA and UA. However, AA and UA oxidize at similar potentials with DA and the result is an overlap of their voltammetric responses when using conventional electrodes. This overlap of potentials has an adverse effect on electrode selectivity and reproducibility [11,12]. In literature, there are many papers reporting the manufacture process and analytical applications involving Sonogels. The Sonogel-Carbon materials were patented and described first by Hidalgo-Hidalgo de Cisneros et al [13,14]. Recently a new type of graphite-based sol-gel electrode has been developed, the sonogel-carbon electrode, which was obtained using high-energy ultrasounds. In general, classical procedures for the synthesis of acid catalysed sol-gel-based electrode materials include the addition of an alcoholic solvent to the initial precursor mixture to make it homogenous. This is followed by the employment of an ultrasound bath for several minutes to promote the hydrolysis. in the other hand, by means of sonocatalysis, high-energy ultrasounds is applied directly to the precursors, and ultrasonic cavitation, sol-gel reactions occur in a unique environnement, leading to gels
AbstractThe Sonogel-Carbon electrode is a special class of sol-gel electrode that exhibits efficient mechanical and electrical properties. In this study, SonogelCarbon modified with L-Histidine was used to prepare a novel electrochemical sensor. This new electrode showed excellent electrocatalytic behavior towards the oxidation of dopamine (DA) in PBS and human serum. The proposed sensor was applied to the simultaneous determination of dopamine, ascorbic acid (AA) and uric acid (UA) in pH 7.4 PBS and excellent results were obtained. A lower detection limit of 1×10 −7 M was achieved. This work, illustrates, for first time, the use of L-histidine Sonogel-Carbon electrode as a simple and low-cost tool for the selective and sensitive determination of DA in the presence of AA and UA.