Droplet array for open-channel high-throughput SERS biosensing.

Open-channel and high throughput are two important aspects of clinical diagnosis, correlation biochemical analysis, cell culture techniques and food safety. Here, we propose the mini-pillar based array for open-channel and high-throughput SERS detection of miRNA. The polydimethylsiloxane (PDMS) mini-pillars are used as a high-throughput platform, which have good anchoring and aggregation effects on microdroplets, greatly reducing the amount of analytical solution and facilitate the homogeneous sample distribution after evaporation. The deposited gold nanorods (Au NRs) on the pillars with optimized diameter served as SERS-active substrate, can greatly improve the sensitivity of SERS signal compared to other planar substrates. On the open-channel biological chip, sensitive, simultaneous, and specific detection of breast cancer marker miRNA-1246 can be performed. In this mini-pillar array SERS system, the limit of detection (LOD) is 10−12 M. The mini-pillar array shows enormous potential for open channel, high-throughput biomolecular detection, providing an opportunity for biomedical point-of-care testing (POCT) and drug screening. We introduced an open-channel mini-pillar based droplet array as a simple SERS platform for high-throughput detecting the miRNAs. Image 1 • A simple mini-pillar based droplet array platform for high-throughput SERS biosensing was proposed. • Mini-pillar arrays can immobilize microdroplets and reduce the dosage of analytical solution. • High-throughput detection of breast cancer marker can be performed on such platform. [ABSTRACT FROM AUTHOR]