Development of a sensitive DMD-based 2D SPR sensor array using single-point detection strategy for multiple aptamer screening

• Published in: Sensors and actuators. B, Chemical Chemical, 2020-02, Vol.305, p.127240, Article 127240
• Main Authors: Wang, Dongping, Chuen Loo, Jacky Fong, Lin, Wei, Geng, Qiang, Shan Ngan, Erika Kit, Kong, Siu Kai, Yam, Yeung, Chen, Shih-Chi, Ho, Ho Pui
• Format: Article
• Language: English
• Subjects: Antibodies; Aptamer screening; Cell death; Diagnostic software; Diagnostic systems; DMD; Screening; Sensitivity; Sensor arrays; Single-point detector; SPR sensor array; Tumor necrosis factor-TNF
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2019.127240

•Single-point detection strategy for 2D SPR sensor array.•High-speed solid-state scanning by digital micro-mirror device (up to 32.5 kHz).•The measured resolution and CV% are 6.47 × 10−6 RIU and 1.45%, respectively.•The system can perform rapid high-throughput aptamer screening.•Screened aptamers can be antibody alternatives for diagnostic and therapeutic purpose. In this paper, we report a novel single-point detection strategy for 2D solid-state angular interrogated SPR (surface plasmon resonance) sensor array for multiple aptamer screening. The scheme operates with two DMDs (digital micro-mirror devices), which suffices a single-point detector for high-throughput 2D SPR measurements without sacrificing the sensitivity. After having verified the biosensing capability of the system, in terms of sensitivity and repeatability, using standard BSA-anti-BSA antibody interaction, we further conducted experiments to perform rapid screening of aptamer candidates for binding with tumor necrosis factor-α (TNF-α). The selected anti-TNF-α aptamers were subsequently evaluated as an in vitro cell protection agent against TNF-α-induced cell death. Our experiments confirm that the anti-TNF-α aptamer screening approach offers high potential as an alternative to that based on antibodies for diagnostic and therapeutic applications.