Sensitive and selective signal-off electrochemiluminescence sensing of prostate-specific antigen based on an aptamer and molecularly imprinted polymer

Specific and sensitive determination of prostate-specific antigen (PSA) in complex real samples holds significant importance as it is an effective molecular biomarker for the clinical diagnosis of prostate cancer. Herein, we constructed a dual-recognition electrochemiluminescence (ECL) sensor based on both the recognition elements of an aptamer and molecularly imprinted polymers (MIP) for the selective and ultrasensitive determination of PSA. The aptamer was self-assembled on gold nanoparticle (AuNP) modified electrodes through Au-S bonds. Subsequently, a layer of MIP membrane was synthesized by electropolymerization of dopamine (DA) to fabricate an aptamer-MIP sensor. After the rebinding of PSA onto imprinted cavities, the ECL response of luminol in the solution decreased. This signal-off strategy was employed for PSA detection with a wide linear range and a low limit of detection of 5 pg mL(-1)-50 ng mL(-1) and 3.0 pg mL(-1), respectively. Compared with individual aptamer sensors, the dual-recognition sensor showed higher specific recognition ability for the determination of PSA. Meanwhile, the good stability, reproducibility, and regenerability endowed the dual recognition sensor with favorable application value in early clinical diagnosis.

Automated summary

A dual-recognition electrochemiluminescence sensor was constructed for the selective and ultrasensitive determination of PSA, combining aptamer and molecularly imprinted polymers as recognition elements. The sensor showed a wide linear range and low detection limit, with higher specific recognition ability compared to individual aptamer sensors. Good stability, reproducibility, and regenerability make the dual recognition sensor valuable in early clinical diagnosis.