Simultaneous Detection of 14 Sweeteners in Pre-prepared Dishes Using High-performance Liquid Chromatography-tandem Mass Spectrometry

In response to the existing methodological gap in direct analysis of sweeteners in ready-to-eat dishes, a novel HPLC-MS/MS-based analytical platform was systematically developed for simultaneous determination of 14 synthetic sweeteners (including acesulfame-K, saccharin, sucralose, etc.) in complex food matrices. This methodology was validated through multi-phase optimization involving matrix-matched calibration, gradient elution protocols, and triple quadrupole mass spectrometric detection. The samples were extracted with 80% methanol-water solution (pH3) under ultrasonic conditions for 10 minutes, followed by centrifugation at 8000 r/min for 5 minutes at 4 ℃. The extraction process was repeated once, and the combined extract was concentrated by rotary evaporation. The concentrated liquid was then diluted to 100 mL, and 5 mL of n-hexane was added. After vortexing for 2 min and purification, the sample was analyzed. The separation process was facilitated by an ACQUITY HSS T3 chromatography column (100 mm×2.1 mm, 1.8 μm), employing a gradient elution technique with two mobile phases: (A) 5 mmol ammonium acetate in 0.1% formic acid aqueous solution and (B) 5 mmol ammonium acetate in 0.1% formic acid methanol solution. For detection, the electrospray negative ion multiple reaction monitoring mode was utilized. The analysis revealed that the 14 sweeteners exhibited strong linear correlations within their respective concentration ranges, with R2 values consistently exceeding 0.999. The detection limits spanned from 0.02 to 4.30 mg/kg, while quantification limits ranged between 0.07 and 14.33 mg/kg. During spiking tests conducted at concentrations of 1.0, 50.0, and 125.0 mg/kg, the recovery rates of the samples fell within the range of 86.2% to 107.1%, accompanied by relative standard deviations (RSD) of less than 10% (n=6). This method demonstrates effective purification, straightforward operation, and high sensitivity, ideal for rapid detection of 14 sweeteners in pre-prepared dishes.