【摘要】 基于COMPASS力场,建立25组对硝基苯酚(4-NP)、3-氨丙基三乙氧基硅烷(APTES)和正硅酸四乙酯(TEOS)的预聚合体系,运用分子动力学方法进行计算模拟。利用径向分布函数及积分数据,筛选出体系4-NP∶APTES∶TEOS的最佳配比为10∶20∶80。实验中,采用水热法合成磁性纳米颗粒,在其表面修饰氨基,与巯基乙酸修饰的碲化镉量子点结合,形成基于硅基表面的磁性量子点。根据分子动力学模拟的结果,以4-NP为模板分子、APTES为功能单体、TEOS为交联剂,按照计算机模拟的配比,在磁性量子点表面合成4-NP分子印迹聚合物,并将其作为传感器的识别元件,成功应用于检测水环境中的4-NP,方法的线性检测范围为5~150 ng/mL,检出限为1 ng/mL,回收率为98.7%~101.2%,相对标准偏差为1.5%~2.4%。更多还原

【Abstract】 Twenty five molecular imprinting prepolymerization systems were performed based on COMPASS force field to optimize the imprinting shell of the fluorescent sensor. The result revealed that the optimum mole ratio of 4-Nitrophenol( 4-NP),3-aminopropyltriethoxysilane( APTES) and tetraethylorthosilicate( TEOS) in this system was 10 ∶ 20 ∶ 80,which was the most stable between template and functional monomer cluster.Uniform magnetite nanaocrystals prepared by hydrothermal method were subsequently embedded in the spherical silica using the reverse microemulsion polymerization. The magnetic silica microspheres were modified with amide groups to adsorb the mercaptoacetic acid capped Cd Te nanocrystals. Finally,according to the results of molecular dynamics simulation, the imprinting shell was anchored on the multifunctional nanocomposites. Under the optimal conditions,a linear relationship between relative fluorescence intensity and concentration of 4-NP was obtained covering the concentration range from 5 to 150 ng/mL with a limit of detection of 1 ng/ml. The feasibility of the fluorescent sensor was successfully evaluated through the analysis of 4-NP in river water. The recoveries were from 98.7% to 101.2%,and the relative standard deviation ranged from 1.5% to 2.4%.更多还原