Combination of magnetic and non-magnetic graphene oxide to develop chemiluminescent aptasensor capable of rapidly quantifying tumor markers

摘要

Rapid and sensitive chemiluminescent aptasensor capable of rapidly sensing tumor markers in human serum with the combination of magnetic and non-magnetic graphene oxide. Human serum (150 μl) containing tumor markers (e.g., AFP and PSA) was mixed in PBS (pH 7.4,10 μl) containing magnetic graphene oxide (MGO) and incubated for 30 minutes to remove various biomolecules acting as interferences of chemiluminescent aptasensor. Then, ssDNA aptamer-conjugated Cy 3 (100 μl), capable of capturing a specific tumor marker, in Tris-HCl buffer (pH 7.5) was added in the solution and incubated for 5 minutes. After the incubation, non-magnetic graphene oxide in Tris-HCl buffer (pH 7.5, 100 μl) was added in the solution to capture free ssDNA aptamers based on the principle of pi-pi stacking interaction. Finally, chemiluminescent aptasensor rapidly quantified tumor markers bound with ssDNA aptamer-conjugated Cy3 when 1,1'-oxalyldiimidazole (ODI) chemiluminescent reagents (e.g., ODI, H_2O_2). The correlation between highly accurate and sensitive chemiluminescent aptasensor and conventional enzyme immunoassay was good. Based on the research results, it is expected that chemiluminescent aptasensors can be developed to early diagnose and prognose various human diseases.