Flow-through Spectrophotometric Sensor for the Determination of Aspartame in Low-Calorie and Dietary Products

Abstract

A very simple flow-through sensor is presented for the determination of the intense sweetener aspartame in low-calorie and dietary products. The sensor is implemented in a monochannel flow-injection system with UV spectrophotometric detection using a Sephadex CM-C25 cationic exchanger packed 20 mm high in a flow cell. This method is based on the transient retention of a cationic species of the sweetener on the solid phase when a pH 5.0 acetic acid sodium acetate buffer (0.01 M) is used as a carrier (2.6 mL(-1) min). The carrier itself elutes the analyte from the solid support, regenerating a sensing zone. Aspartame was determined by measuring its intrinsic absorbance at 219 nm at its residence time without any derivatization. Calibration graphs were linear over the range of 5.0 - 600.0 microg mL(-1) with an RSD of 0.55% (peak height). This sweetener was determined in several samples by measuring the height or peak area, obtaining recoveries ranging between 95 - 101% and 97.5 - 101%, respectively. The procedure was validated for its use in the determination of aspartame in low-calorie and dietary products, giving reproducible and accurate results.

Identification and characterisation of the E951 artificial food sweetener by vibrational spectroscopy and theoretical modelling

“…3d). [27,47,56,66] In the Raman spectra in the acidic pH range 2-0 (Fig. S3, Table S3 in Supporting Information), new bands appear in the low wavenumber region (700-200 cm −1 ) and are attributed to the carboxylate bending mode (pH 1, 650 cm −1 ), [32] phenylalanine and Amide IV vibrations (pH 1, 624 cm −1 ), [42] Amide VI and C1OO − wagging mode (pH 1, 601 cm −1 ), [32,42] N-C O bending mode and primary saturated aliphatic amides (pH 1, 581 cm −1 ), [67] COO − bending mode (pH 1, 524, 333 cm −1 ), [32,67] ring out-ofplane bending mode (pH 1, 478 cm −1 ).…”

Bienzymatic Biosensor for Rapid Detection of Aspartame by Flow Injection Analysis

“…High performance liquid chromatography (HPLC) is widely used for the determination of sweeteners [5–7], 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 [8–10], 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.…”

Recent trends in solid phase spectrometry: 2003–2009. A Review

“…(N-L-α-aspartyl-Lphenylalanine-1-methyl ester) (AS) in sweets and drinks [88], and Acesulfame-K (6-methyl-1,2,3-oxathiazin-4(3H)-one-2,2-dioxide) (AK) in tabletop sweeteners [89]. Their FI-SPS system was also used for the determination of AS in low-calorie foods and dietary products [90] and SA in low-calorie foods, but without separation [91]. Diphenylamine residues in apple and pear can also be determined by FI-SPS [64].…”