Bridging Fe3O4@Au nanoflowers and Au@Ag nanospheres with aptamer for ultrasensitive SERS detection of aflatoxin B1. (15th September 2020)

• Record Type: Journal Article
• Authors: He, Huirong; Sun, Da-Wen; Pu, Hongbin; Huang, Lunjie
• Is Part Of: Food chemistry. Volume 324(2020)
• Publication Date: 2020-09-15
• Subjects: Aflatoxin B1 (AFB1) -- Peanut oil -- Surface-enhanced Raman spectroscopy (SERS) -- Aptamer -- Capture probes -- Reporter probes -- 4-mercaptobenzoic acid (4-MBA); Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2020.126832
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Multifunctional Fe3 O4 @Au nanoflowers have been successfully synthesized. Au-4MBA@Ag nanospheres with stable and strong SERS signal was prepared as SERS tag. High-performance SERS aptasensor was successfully developed by aptamer recognition. The ultralow detection limit of AFB1 was estimated to be 0.40 pg·mL −1. Abstract: Aflatoxin B1 (AFB1) as the most toxic mycotoxin in contaminated food can greatly threaten human health, and sensitive and selective detection of AFB1 is thus highly desired. An ultrasensitive surface-enhanced Raman spectroscopy (SERS) aptasensor was developed for AFB1 detection in peanut oil samples. SH-cDNA modified Fe3 O4 @Au nanoflowers acted as capture probes, SH-Apt modified Au@Ag nanospheres and commercial Cy3-Apt were used as reporter probes. Strong SERS signals of reporter probes were produced due to the recognition of AFB1 aptamer and its complementary strand (SH-cDNA). With the preferred binding of AFB1 aptamer to AFB1, reporter probes were released from capture probes, causing a linear decrease in SERS intensity. Therefore an ultralow detection limit of 0.40 pg·mL −1 in a wide linear range of 0.0001–100 ng·mL −1 was obtained and the sensibility of this SERS aptasensor was higher than that of the Cy3-Apt based SERS aptasensor. In addition, an excellent selectivity in interfering toxins and satisfactory recoveries of 96.6–115% in peanut oil samples were obtained, proving this aptasensor is a promising analytical tool in AFB1 detection.