Highly selective and label-free Love-mode surface acoustic wave biosensor for carcinoembryonic antigen detection using a self-assembled monolayer bioreceptor

• Published in: Applied surface science 2020-07, Vol.518 (C), p.146061, Article 146061
• Main Authors: Jandas, P.J., Luo, Jingting, Quan, Aojie, Qiu, Chuanghua, Cao, Weiguo, Fu, Chen, Fu, Yong Qing
• Format: Article
• Language: English
• Subjects: Biosensing; CEA; Label free; Piezoelectricity; SAM; SAW
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2020.146061

[Display omitted] •Real-time detection of CEA using SAW device.•Obtained a limit of detection of 0.31 ng/ml of CEA.•SAW devise for anti-CEA with minimum increase in insertion loss under liquid state analysis.•High selectivity towards CEA from a mixture of similar tumour marking proteins.•High stability over 30 days with only around 8% performance lose.•Validated using Langmuir and Freundlich sorption isotherms. A Love-mode surface acoustic wave (SAW) biosensor based on ST-cut quartz was developed for highly selective and label-free detection of carcinoembryonic antigen (CEA). The delay line area of an interdigital transducer (IDT) based SAW device was coated with gold and then chemically modified through thioglycolic acid–EDC/NHS reaction mechanism. A self-assembled monolayer of anti-CEA was further immobilized on the bioreceptors through the coupling layer. The biosensing capability of the SAW device was evaluated using solutions of CEA with various concentrations and limit of detection was obtained at 0.31 ng/ml of CEA, which is better than the results reported by the literatures available for CEA detection using SAW device. The real-time detection capability of the biosensor was evaluated using clinical serum samples and selectivity was evaluated using mixed solutions of CEA with other common tumor marking proteins. Long-term stability of the biosensor was also evaluated over a period of 30 days and the immunoassay response has shown only 8% decrease in performance within the whole period. The binding of CEA onto the bioreceptor was evaluated through Langmuir and Freundlich sorption isotherm kinetic studies as well.