The results of SERS suggested that PEI and uracil are competitively adsorbed instead of co-adsorbed on the silver surface, and the adsorption capacity of PEI is stronger than that of uracil.

• SERS结果表明，在银电极表面，尿嘧啶与PEI之间的吸附行为为竞争吸附，而非共吸附，且PEI的吸附能力强于尿嘧啶。