Molybdenum disulfide-based aptamer sensor for high-precision detection of prostate specific antigen in serum

As a representative transition metal dichalcogenide, molybdenum disulfide (MoS2) has unique electronic, optical, and mechanical properties that exhibit advantages in the construction of biosensing interfaces. In this study, we explored the construction of a MoS2-based aptamer sensor and investigated its application for high-precision detection of prostate specific antigen (PSA) in serum. Carboxyl group-modified MoS2 was stably bonded to the surface of an aminated electrode as a substrate structure, and the electrode was further modified with biocompatible membrane polydopamine and PSA aptamers to form an aminated screen-printed electrode/carboxylated MoS2/polydopamine (SPE-NH2/MoS2-COOH/PDA)-based aptamer sensor, which achieved ultrasensitive detection of PSA at 0.001 pg/mL similar to 1 ng/mL with a limit of detection (LOD) of 0.16 fg/mL. The detection results of related interfering substances, such as L-cysteine, alpha fetoprotein (AFP), carcinoembryonic antigen (CEA) and bovine serum albumin (BSA), proved that the sensor had good selectivity. Then, repeated test results of multiple sensors verified that the aptamer sensors had good reproducibility between sensors. Finally, the practical application of the aptamer sensor was evaluated by a blank spiking method, which demonstrated its great clinical application potential. In summary, our study has provided ideas for the application of MoS2 composite-based aptamer sensing interfaces for potential precision medicine needs.