Each movement in the li
In the last decades, the high-intensity sweeteners have increasingly been used by the food and pharmaceutical industries to improve the taste of different products. Despite the long-term usage of artificial high-intensity sweeteners like aspartame, saccharin, neotame, acesulfame potassium and sucralose, their safety is still debated and currently European Food Safety Agency (EFSA) is conducting a full re-evaluation process of aspartame under the mandate of the European Commission [1]. Toxicological and clinical studies indicate that an excess of artificial sweeteners induces various health problems such as memory loss, headaches, seizures, cancer, etc. [2�C4]. In consequence, the analysis of sweeteners in foods and pharmaceutical preparations is important for health consumer protection.

Various analytical techniques have been applied in the analysis of natural sugars and artificial sweeteners. High performance liquid chromatography (HPLC) is widely used for the determination of sweeteners [5�C7], but this technique is based on expensive equipment, requires long and complex sample pretreatment, uses toxic organic solvents and various reagents. Different alternative analytical methods based on various detections, such as electrochemical [8�C10], spectrophotometric [11,12], chemiluminescent [13] or colorimetric detection [14,15] have been developed. Even if these techniques require simple equipment, some of them are time-consuming, involve different chemical reagents, or do not have the necessary selectivity for the analyte determination in relevant commercial samples.

(Bio)sensors are interesting analytical devices with good analytical performance for the rapid analysis of complex samples [16,17]. Only few papers describe biosensors for the determination of aspartame in soft drinks. Those biosensors were based on the Cilengitide chemical co-immobilization of enzymes on different electrodes, such as ammonia-gas-sensing electrode [18], platinum-based hydrogen peroxide electrode [19], oxygen electrode [20], or graphite epoxy composite electrode [21]. Another strategy is based on the enzyme immobilization into columns integrated in flow systems: two enzyme columns containing peptidase and aspartate aminotransferase, respectively, immobilized on activated aminopropyl glass beads and an L-glutamate oxidase electrode [22] or another system consisting of a column containing pronase and an L-amino acid oxidase electrode [23]. These biosensors require long analysis times, show a reduced linear range, short lifetimes, or weak detection limits. Thus, fast, inexpensive methods of analysis with improved selectivity and sensitivity are required to monitor sweeteners in an extensive range of different commercial product matrices.