title: A compact imaging spectroscopic system for biomolecular detections on plasmonic chips.
abstract: In this study, we demonstrate a compact imaging spectroscopic system for high-throughput detection of biomolecular interactions on plasmonic chips, based on a curved grating as the key element of light diffraction and light focusing. Both the curved grating and the plasmonic chips are fabricated on flexible plastic substrates using a gas-assisted thermal-embossing method. A fiber-coupled broadband light source and a camera are included in the system. Spectral resolution within 1 nm is achieved in sensing environmental index solutions and protein bindings. The detected sensitivities of the plasmonic chip are comparable with a commercial spectrometer. An extra one-dimensional scanning stage enables high-throughput detection of protein binding on a designed plasmonic chip consisting of several nanoslit arrays with different periods. The detected resonance wavelengths match well with the grating equation under an air environment. Wavelength shifts between 1 and 9 nm are detected for antigens of various concentrations binding with antibodies. A simple, mass-productive and cost-effective method has been demonstrated on the imaging spectroscopic system for real-time, label-free, highly sensitive and high-throughput screening of biomolecular interactions.
authors.affiliation: Department of Applied Materials and Optoelectronics Engineering, National Chi Nan University, Nantou 54561, Taiwan. wstsai@ncnu.edu.tw.
authors.forename: Shu-Cheng
authors.initials: SC
authors.lastname: Lo
authors.affiliation: Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan.
authors.forename: En-Hung
authors.initials: EH
authors.lastname: Lin
authors.affiliation: Research Center for Applied Sciences, Academia Sinica, Taipei 11529, Taiwan.
authors.forename: Pei-Kuen
authors.initials: PK
authors.lastname: Wei
authors.affiliation: Department of Applied Materials and Optoelectronics Engineering, National Chi Nan University, Nantou 54561, Taiwan. wstsai@ncnu.edu.tw.
authors.forename: Wan-Shao
authors.initials: WS
authors.lastname: Tsai
mesh_terms: D000906:Antibodies / Q000032:analysis*; D000941:Antigens / Q000032:analysis*; D057166:High-Throughput Screening Assays; D011485:Protein Binding; D012031:Refractometry; D013057:Spectrum Analysis
chemical_list: D000906:Antibodies; D000941:Antigens