A DNA tweezers fluorescence aptasensor based on split aptamer -assisted magnetic nanoparticles for the detection of enrofloxacin in food. (March 2023)

• Record Type: Journal Article
• Authors: Shang, Zixuan; Ma, Pengfei; Khan, Imran Mahmood; Zhang, Yin; Wang, Zhouping
• Is Part Of: Food control. Volume 145(2023)
• Publication Date: 2023-03
• Subjects: Enrofloxacin detection -- Split aptamer -- Sandwich structure -- Magnetic separation -- DNA tweezers -- Animal-derived food; Food -- Quality -- Periodicals; Food -- Analysis -- Periodicals; Food handling -- Periodicals; Food industry and trade -- Quality control -- Periodicals; Aliments -- Industrie et commerce -- Qualité -- Contrôle -- Périodiques; Aliments -- Qualité -- Périodiques; Aliments -- Analyse -- Périodiques; Hygiène alimentaire -- Périodiques; Food -- Analysis; Food handling; Food -- Quality; Periodicals; Electronic journals; 664.07
• DOI: 10.1016/j.foodcont.2022.109437
• Languages: English
• ISSNs: 0956-7135

Abstract

Abstract: A DNA tweezers fluorescence aptasensor based on split aptamer assisted-magnetic nanoparticles (MNPs) and magnetic separation was established for the detection of Enrofloxacin (ENR). The DNA tweezers' fluorescence aptasensor consists of two arms with fluorophores (FAM) and quenchers (BHQ1 ) connected at both ends. Meanwhile, the high fluorescence signal can be generated with FAM and BHQ1 being spatially separated. Split aptamer 1 (SPA1 ) of ENR was annealed and incubated with avidin-coated MNPs. ENR and split aptamer 2 (SPA2 ) were added to form a sandwich structure with two split aptamer strands (MNPS-SPA1 /ENR/SPA2 ). After magnetic separation, the supernatant did not interact with DNA tweezers, which made DNA tweezers a "turn-on" aptasensor to enhance the fluorescence signal. In the absence of ENR, SPA2 was free in the supernatant to dramatically quench the fluorescence which made DNA tweezers a "turn-off" aptasensor. The linear range of ENR detection was 0.01–100 ng/mL with a limit of detection of 0.008 ng/mL. The prepared DNA tweezers fluorescence aptasensors were applied to detect ENR in spiked milk samples, which showed good recoveries between 90.27% and 106.62%. In addition, the present method showed great potential for the target, employing a split aptamer detection platform in practical application. Highlights: A novel fluorescence aptasensor assay for Enrofloxacin (ENR) detection was established. The sandwich structure is formed by specific target recognition of split aptamer to achieve sensitive detection. The "turn-on/turn-off" structure of DNA tweezers offers significant fluorescence signals.