There are many aspects of influence factors of sodium tungstate and dioxopromethazine hydrochloride system.

1. The influence of reagent adding order: after polycondensation of tungsten acid radical in acidic solution, the effect of dioxopromethazine hydrochloride is better. 

2. The influence of the medium: in H3PO4 and B-R medium, system resonance light scattering signal obviously enhances, which has the highest sensitivity in H3PO4 medium system.

3. The influence of the concentration of sodium tungstate: as shown in the figure, when sodium tungstate concentration is low, ionic association concentration is small and resonance light scattering intensity of solution is weak. With the increase of concentration of sodium tungstate solution, it is conducive to the formation of the ion association content. Sodium tungstate and dioxopromethazine hydrochloride gradually reach the maximum and increase stability.

4. The influence of temperature: research the effect of three temperatures  0℃, room temperature (25℃) and 50℃ on the system. Results show that the scattering intensity of the three temperature blank solution did not change, but the system was slightly higher than the room temperature at 0 ℃. It shows that low temperature could reduce the dispersion of particles of associating content in solution and benefit ion association reaction so as to generate more ion of associating. At 50℃, the system of resonance light scattering signal basically disappears.  

5. The influence of surfactant: CTMAB and CPB will make tungsten acid radical associate which is not conducive to the formation of ion association content. SDS, SLS, SDBS make the system of the scattering signal almost disappear which is the result of playing the solubilization. PVA generates a certain amount of scattering signal of sodium tungstate solution and reduce the intensity of resonance light scattering system.

6. The influence of water-soluble organic solvent: the addition of ethanol, acetone, will have little impact on blank value. But the system resonance light scattering intensity sharply reduces. And the effect of acetone is better than ethanol.

7. The influence of coexisting substance: common inorganic ions, sugar, protein and amino acid are allowed to exist in high concentration without interference measurement. So the method is still has good selectivity.