Construction of Fluorescence Sensing Platform on the Basis of Molybdenum Disulfide Nanosheet for the Detection of AFB<sub>1</sub>

Abstract

Purpose: Aflatoxin B 1 is the most common mycotoxin in cereal crops; it is of stronger toxicity and has a carcinogenic effect. In recent years, a series of fluorescence sensors constructed on the basis of MoS 2 NS fluorescence quenching property have become a research hotspot. Therefore, we can construct a fast and simple analysis method with high specificity to detect AFB 1 by utilizing MoS 2 NS, which can be effectively applied to food safety monitoring and clinical diagnosis. Method: In the current research, a fluorescence biosensor is developed on the basis of a new type of two-dimensional nano-material namely MoS 2 NS applied for the detection of AFB 1 . The fluorescence of Apt@AFB 1 can be quickly quenched by MoS 2 NS through the fluorescence resonance energy transfer (FRET). When the target molecule AFB 1 exists, after the specificity binding between AFB 1 and aptamer, the Apt@AFB 1 loses its single stranded structure and is away from MoS 2 NS, and the fluorescence of Apt@AFB 1 cannot be quenched effectively. Such sensing signals can be used to achieve the sensitive detection of AFB 1 . Result: With this new method, under the optimized conditions, the AFB 1 is analyzed in the MoS 2 NS/Apt@AFB 1 sensing platform. Within the dynamic range of 0.2 -25 ng/mL, the sensing platform expresses a good linear response to the level of AFB 1 with the R 2 = 0.9964 and LOD as 90 pg/mL. This method is applied to detect the actual serum samples and soybean milk with the recovery rate of 93.10% -107.23% and 95.15% -102.60% separately, and it can be used in the quantitative detection under the interference of other mycotoxins in a relatively accurate way. Conclusion: It is proved that this new detection method can be used as a potential biosensor platform for the detection of AFB 1 . This detection method features several advantages such as specificity, rapidness and low costs, which can meet the requirement of trace detection in clinical detection and food safety.

Synthesis and Sensing Performance of Chitin Fiber/MoS2 Composites

“…Among chitin and its derivatives, spun chitin fibers have good air permeability and a high specific surface area, as well as good biocompatibility, and have been used in a large number of medical materials and apparel [52,53]. As a metal sulfide two-dimensional material, molybdenum disulfide (MoS 2 ) has a layer structure similar to that of graphite and is maintained by relatively weak van der Waals forces between the layers, exhibiting many excellent properties [54,55]. In this work, for the recycling of waste chitin fiber (CF) materials and the functional development of chitin materials, a one-step hydrothermal method was used to prepare MoS 2 , hydrothermal chitin fibers (H-CFs), and chitin molybdenum disulfide composite material (MoS 2 /CFs); these materials were prepared in order to extend the application of chitin materials in the field of gas sensing and that of sensing properties in other fields, in combination with MoS 2 two-dimensional materials, and to avoid the high energy consumption problem encountered during the MoS 2 synthesis process.…”