核壳型磁性纳米粒子界面氨基的测定

Detection of Amino-Group on the Surface of Core-Shell Magnetic Nanoparticles

目的:应用对硝基苯甲醛比色测定法测定磁性纳米粒子界面修饰的氨基。方法:合成核壳型磁性纳米粒子,并用AEAPS(氨乙基氨丙基聚二甲基硅氧烷)修饰其界面氨基,然后采用对硝基苯甲醛比色测定法测定不同反应条件下的磁性纳米粒子界面的氨基。结果:采用对硝基苯甲醛比色测定法可以测出在磁性纳米粒子界面连接的氨基量,不同反应条件下氨基连接量不同,氨基在磁性纳米粒子上的浓度为5.90至33.44nmol/mg,最大相对量为1.63 umol/m^2。结论:对硝基苯甲醛比色法不仅可以定量测定磁性纳米粒子界面氨基量,而且可以研究反应条件对磁性纳米粒子界面氨基的连接量的影响。

Objective： To investigate linking amount of amino- groups on the surface of magnetic nanoparticles using p-nitrobenzaldehyde colorimetric titration method. Method： Core-shell magnetic nanoparticles were first synthesized, and then amino group on their surface was modified with aminoethylaminopropyl poly（dimethyl siloxane）（ AEAPS ）, at last the linking amount of amine groups on the surface of magnetic nanoparticles under different conditions were determined by p-nitrobenzaldehyde colorimetric titration method. Results： The amount of amine- groups On the surface of nanoparticles could be estimated by p-nitrobenzaldehyde colorimetric titration method. The amine groups density on magnetic nanoparticles lied between 5.90 to 33.44 nmol/mg, the maximum relative density was 1.63 umol/m：. Conclusion： P-nitrohenzaldehyde colorimetric titration method can be used not only to quantitate amount of amino groups on the surface of nanoparticles but also to evaluate the influence of reaction conditions on linking rate.