The absorption properties of Cy3 fluorescent probe reagents with carboxyl groups on the surface are measured by using the principle of multi-scattering of light of uniformly dispersed nanospheres in solution. By adding SiO

2

microsphere random scattering medium into Cy3 aqueous solution

the incident light will be scattered multiple times when passing through the random medium

and the light path through the detection solution will be increased

thus enhancing the absorption of sample detection. The results show that with the increase of the concentration of SiO

2

nanospheres with diameter of 200 and 400 nm

the light scattering of the solution is enhanced continuously

and the absorption intensity of the fluorescent dye Cy3 aqueous solution in

creases by 1. 63 times and 1. 82 times

respectively.