DNA-based functionalization of two-dimensional MoS2 FET biosensor for ultrasensitive detection of PSA

• Published in: Applied surface science Vol. 548; p. 149169
• Main Authors: Zhang, Yi, Feng, Dezhi, Xu, Yi, Yin, Ziwei, Dou, Wei, Habiba, UM E, Pan, Changyi, Zhang, Zongkun, Mou, Hao, Deng, Huiyong, Mi, Xianqiang, Dai, Ning
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.05.2021
• Subjects: Biosensor; Field-effect transistor; Molybdenum disulfide; Surface functionalization; Two-dimensional materials; Two-dimensional materials; Surface functionalization; Molybdenum disulfide; Field-effect transistor; Biosensor
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2021.149169

[Display omitted] •The device has a wide linear range of 1fg/mL to 100ng/mL.•The biosensor could detect PSA at 1fg/mL in a clinically relevant sample of serum.•The MoS2 bio-FET is demonstrated for excellent specificity detection of PSA.•The proposed DNA-based modification technique is ecofriendly and universal.•The PSA in this novel bio-functional system might be substituted by other analytes. Molybdenum disulfide (MoS2) field-effect transistor (FET) biosensors are being increasingly studied due to their highly sensitive and label-free biodetection, system-level integration and easy fabrication. However, the stability and detection ability of a pristine device deteriorate due to the absorption of H2O and CO and usually exhibit high false signals. Herein, a novel ecofriendly technology is employed to functionalize MoS2 FETs using the conjugation of a DNA tetrahedron and biotin-streptavidin (B-SA). The functionlized devices demonstrate ultrahigh sensitivity of the target protein (prostate-specific antigen, PSA) with a limit of detection of 1fg/mL and a wide linear range of 1fg/mL to 100ng/mL in a phosphate-buffered saline, which are 100 and 10,000 times higher than the reported highest values, respectively; these results are attributed to the stable immobilization provided by the DNA tetrahedron as well as the multilevel amplification and anchor system (B-SA system), which improves the antibody-antigen (Ab-Ag) binding. Real-time measurement results indicate that our proposed biosensor can also detect trace PSA (1fg/mL) in a clinically relevant sample of healthy human serum.