Multivalent aptasensor array and silver aggregated amplification for multiplex detection in microfluidic devices

• Published in: Talanta (Oxford) Vol. 188; pp. 417 - 422
• Main Authors: Liu, Xiaohui, Li, Hui, Zhao, Yaju, Yu, Xiaodong, Xu, Danke
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.10.2018
• Subjects: Aptamer; Microarray; Microfluidic; Multiplex detection; Silver nanoparticles; Aptamer; Microarray; Multiplex detection; Silver nanoparticles; Microfluidic
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2018.05.048

Herein, we developed a rapid and sensitive aptamers-based sandwich assay in microfluidic devices based on multivalent aptasensor array (MAA) chip and silver aggregated amplification (SAA) strategy for the detection of two biomarkers. Firstly, aptamers-modified silver nanoparticles were dotted in array to form MAA chip. Then PDMS was used to form a microfluidic device. After that, target proteins and two kinds of aptamer-modified silver nanoparticles (Tag-A and Tag-B) were rapidly injected into the microfluidic device. The aptamer on MAA chip recognized target, and the target also bound with Tag-A and Tag-B which could aggregate with each other to amplify fluorescence signal. Based on MAA chip and SAA strategy in microfluidic device, a linear response to PDGF-BB (r = 0.999) was obtained in the concentration range from 16 pg mL−1 to 250 ng mL−1, and the detection limit was 1.4 pg mL−1. In addition, a linear response to PDGF-BB (r = 0.992) was obtained in the concentration range from 16 pg mL−1 to 250 ng mL−1 in 10% blood serum with detection limit of 7.8 pg mL−1. Ultimately, this assay was used to simultaneously detect PDGF-BB and VEGF-165, and the results showed good specificity and sensitivity. This assay can also be expanded to sensitive and high-throughput detection of other protein biomarkers by coupling of various aptamers with nanoparticles. Schematic 1. Schematic illustration of the SAA strategy with microfluidic devices for the detection of protein. We developed a rapid and sensitive aptamers-based sandwich assay in microfluidic devices based on multivalent aptasensor array (MAA) chip and silver aggregated amplification (SAA) strategy for the detection of two biomarkers at the same time. Based on MAA chip and SAA strategy in microfluidic device, the detection limit for PDGF-BB was 1.4 pg mL−1 in buffers and 7.8 pg mL−1 in 10% serum. Additionally, this assay was used to simultaneously detect PDGF-BB and VEGF-165 with good specificity and sensitivity. [Display omitted] •A rapid and sensitive aptamers-based sandwich assay based on MAA chip and SAA strategy in microfluidic was developed.•It was a sensitive and rapid platform for simultaneously detection of PDGF-BB and VEGF-165.•The platform exhibited a broad linear range from 16 pg mL−1 to 250 ng mL−1 with detection limit of 1.4 pg mL−1.•The platform can be expanded to sensitive and high-throughput detection of other protein biomarkers.