Method for determining trivalent arsenic by using resonance scattering spectrometry

The invention discloses a method for determining As (III) by using resonance scattering spectrometry. The principle is as follows: when the arsenic nucleic acid aptamer and diaminotriphenylmethane dyemalachite green are combined together, the average particle size of assembled and stacked nanoparticles is about 500 nm, and at the moment, after As (III) is added, the particle size of the nanoparticles can be increased along with the increase of the adding amount of As (III). The particle size of the nanoparticle and the resonance scattering signal are in a forward relation, so that As (III) can be detected by analyzing the change of the resonance scattering signal. Compared with an existing method, the method has the advantages that instruments are simple, operation is easy, convenient andrapid, reagents are easy to obtain, and sensitivity is high. 本发明公开了一种用共振散射光谱法测定As（Ⅲ）的方法。其原理是：当砷核酸适配体与二氨基三苯甲烷类染料孔雀绿组合在一起时，组装堆积出来的纳米粒子的平均粒径为500nm左右，此时As（Ⅲ）的加入后，纳米粒子的粒径会随着As（Ⅲ）的加入量增加而变大。纳米粒子的粒径大小与共振散射信号成正向关系，所以通过分析共振散射信号的变化，就可以实