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文獻名： A magnetic relaxation switch sensor for determination of 17βEstradiol in milk and eggs based on aptamerfunctionalized Fe₃O₄@Au nanoparticles

 

 

作者： Xin Wang, Kaili Pei, Hanying Sun, Qi Wang

School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai, China

 

摘要：

BACKGROUND

A simple and rapid detection method for 17β-estradiol (E₂) in complex food matrix is greatly desirable. A magnetic relaxation switch (MRS) sensor for detecting E₂ based on the aptamer-functionalized gold-coated iron oxide (Fe₃O₄@Au) nanocomposite was designed in this study. Fe₃O₄@Au nanoparticles (NPs) played as a ‘switch’ between dispersed and aggregated states, while aptamer served as the recognition unit.

RESULTS

According to the sensing effect of monocomponent relaxation time (T_2W) for E₂, the volume ratio of aptamers to Fe₃O₄@Au, the sodium chloride (NaCl) concentration, the concentration of Fe₃O₄@Au@Apt, and reaction time were optimized to be 4:1, 0.03 mol L^–1, 4 μmol L^–1 and 15 min, respectively. For the analysis of food sample, the E₂ was quantified over a concentration range of 1 to 100 nmol L^–1 with a detection limit of 7.6 nmol L^–1 for milk samples, while a linearity range of 20 to 100 nmol L^–1 and a detection limit of 8.57 nmol L^–1 for egg samples.

 

 

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