- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Turn-On Fluorescence Aptasensor on Magnetic Nanobeads for Aflatoxin M1 Detection Based on an Exonuclease III-Assisted Signal Amplification Strategy
摘要： In order to satisfy the need for sensitive detection of Aflatoxin M1 (AFM1), we constructed a simple and signal-on fluorescence aptasensor based on an autocatalytic Exonuclease III (Exo III)-assisted signal amplification strategy. In this sensor, the DNA hybridization on magnetic nanobeads could be triggered by the target AFM1, resulting in the release of a single-stranded DNA to induce an Exo III-assisted signal amplification, in which numerous G-quadruplex structures would be produced and then associated with the fluorescent dye to generate significantly amplified fluorescence signals resulting in the increased sensitivity. Under the optimized conditions, this aptasensor was able to detect AFM1 with a practical detection limit of 9.73 ng kg?1 in milk samples. Furthermore, the prepared sensor was successfully used for detection of AFM1 in the commercially available milk samples with the recovery percentages ranging from 80.13% to 108.67%. Also, the sensor performance was evaluated by the commercial immunoassay kit with satisfactory results.
关键词： aptasensors,signal amplification,G-quadruplex,magnetic nanobeads,aflatoxin M1
更新于2025-09-23 15:22:29
-
Lateral flow immunoassays combining enrichment and colorimetry-fluorescence quantitative detection of sulfamethazine in milk based on trifunctional magnetic nanobeads
摘要： In this study, magnetic nanobeads (MNBs) were used as a trifunctional material in lateral flow immunoassay for quantitative detection of sulfamethazine (SM2) in milk. Magnetic enrichment aimed to reduce matrix effects. Naked-eye screening of SM2 was based on colorimetry of colored MNBs. The cut-off value of the naked-eye screening was 25 ng mL-1. When the concentration of SM2 in the samples is equal to the cut-off value or higher, the lateral flow strips can be quantitatively detected via grayscale intensity based on colored MNBs. When the concentration of SM2 in the samples is less than the cut-off value, the lateral flow strips can be quantitatively detected by means of fluorescence intensity based on the fluorescence quenching effect of MNBs. Under optimal conditions, the linear range and limit of detection (LOD) of fluorescence lateral flow immunoassay were 0.033-33 ng mL-1 and 0.026 ng mL-1 respectively, while the linear range and LOD of colorimetric lateral flow immunoassay was 1-100 ng mL-1 and 0.71 ng mL-1, respectively. This novel method can be used for rapid and quantitative detection of SM2 in milk.
关键词： lateral flow immunoassay,matrix effects,magnetic nanobeads,colorimetry,fluorescence,sulfamethazine
更新于2025-09-10 09:29:36