Surface stress-based biosensor with stable conductive AuNPs network for biomolecules detection

• Published in: Applied surface science Vol. 491; pp. 443 - 450
• Main Authors: Zhao, Dong, Liu, Yan, Zhang, Qiang, Zhang, Yixia, Zhang, Wendong, Duan, Qianqian, Yuan, Zhongyun, Zhang, Riguang, Sang, Shengbo
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.10.2019
• Subjects: Biosensor; Glucose detection; SC-AuNW; Surface stress; SC-AuNW; Glucose detection; Surface stress; Biosensor
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2019.06.178

The composite of gold and PDMS hold remarkable potential for surface stress-based biosensor applicaitons. However, the gold and PDMS in composite suffers from poor compatibility with each other and suppresses the performance of the biosensor. Here, we conduct two-step synthesis of the composite of gold and PDMS by in-situ reduction and glucose reduction of HAuCl4. The composite shows stable conductive gold nanoparticle network (SC-AuNW). In in-situ reduction, Au-seeds are embedded in PDMS surface. Furthermore, AuNPs are also generated inside the PDMS and enhance conductivity. The SC-AuNW plays a crucial role in tunneling conductivity of composite film and exhibits an excellent sensitivity to surface stress. We construct SC-AuNW-PDMS biosensors based on surface stress for glucose detection with a detection limit of 0.021 mM, high repeatability and specificity. Our research can promote the application of flexible conductive films in biosensors for disease diagnosis. •The PDMS film with stable conductive gold network on surface was synthesized.•The film was sensitive to surface stress due to its tunneling conductivity.•The film with GOx-modified interface can specifically detect the glucose.