title: Low auto-fluorescence fabrication methods for plastic nanoslits.
abstract: Plastic nanofluidic devices are becoming increasingly important for biological and chemical applications. However, they suffer from high auto-fluorescence when used for on-chip optical detection. In this study, the auto-fluorescence problem of plastic nanofluidic devices was remedied by newly developed fabrication methods that minimise their auto-fluorescence: one by depositing a gold (Au) layer on them, the other by making them ultra-thin. In the first method, the Au layer [minimum thickness is 40 nm on 150 μm SU-8, 50 nm on 1 mm polyethylene terephthalate (PET), and 40 on 2 nm polymethyl methacrylate (PMMA)] blocks the auto-fluorescence of the polymer; in the second method, auto-fluorescence is minimised by making the chips ultra-thin, selected operating thickness of SU-8 is 20 μm, for PET it is 150 μm, and for PMMA it is 0.8 mm.
authors.affiliation: Key Laboratory for Micro/Nano Technology and Systems of Liaoning Province, Dalian University of Technology, Dalian 116024, People's Republic of China.
authors.forename: Zhifu
authors.initials: Z
authors.lastname: Yin
authors.affiliation: Department of Biomedical Engineering, Dalian University of Technology, Dalian 116024, People's Republic of China.
authors.forename: Liping
authors.initials: L
authors.lastname: Qi
authors.affiliation: Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education, Dalian University of Technology, Dalian 116024, People's Republic of China. zouhl@dlut.edu.cn.
authors.forename: Helin
authors.initials: H
authors.lastname: Zou
authors.affiliation: Key Laboratory for Micro/Nano Technology and Systems of Liaoning Province, Dalian University of Technology, Dalian 116024, People's Republic of China.
authors.forename: Lei
authors.initials: L
authors.lastname: Sun
authors.affiliation: Key Laboratory for Micro/Nano Technology and Systems of Liaoning Province, Dalian University of Technology, Dalian 116024, People's Republic of China.
authors.forename: Shenbo
authors.initials: S
authors.lastname: Xu
mesh_terms: D004129:Dimethylpolysiloxanes / Q000737:chemistry; D004867:Equipment Design; D005453:Fluorescence; D006046:Gold / Q000737:chemistry; D056656:Lab-On-A-Chip Devices; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation; D055616:Microtechnology / Q000379:methods*; D049329:Nanostructures / Q000737:chemistry*; D009757:Nylons / Q000737:chemistry; D010969:Plastics / Q000138:chemical synthesis* / Q000737:chemistry; D019904:Polymethyl Methacrylate / Q000138:chemical synthesis / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry
chemical_list: D004129:Dimethylpolysiloxanes; D009757:Nylons; D010969:Plastics; C085707:poly(dimethylsiloxane)-polyamide copolymer; D006046:Gold; D012822:Silicon Dioxide; D019904:Polymethyl Methacrylate