title: Fluorescence enhancement and multiple protein detection in ZnO nanostructure microfluidic devices.
abstract: In this study, different morphological ZnO nanostructures, those of sharp nanowires (NWs), rod NWs, and hexahedral-puncheon nanostructures, were grown in microfluidic channels on the same glass substrate. Characterizations of correspondent biomolecule binding properties were simulated and demonstrated. The surface was modified using 3-ammineopropyl-triethoxysilane (3-APTES) and biotin-N-hydroxysuccinimide ester (NHS-biotin). Different concentrations (4.17pM to 41.7nM) of dye-conjugated streptavidin were simultaneously infused through the second microfluidic channels, which lie 90° from the first microfluidic channels. The florescent intensity at the crossover areas showed good agreement with simulations, with sharp ZnO NWs exhibiting the largest dynamic range and the highest fluorescent intensity. We further characterize correspondent protein detection using sharp ZnO NWs. The surfaces of these ZnO NWs were modified with mouse immunoglobulin G (IgG), infused through the second microfluidic channels with dye-conjugated (Alexa 546) anti-mouse IgG in different concentrations. Concentrations ranging from 417fM to 41.7nM can be resolved using sharp ZnO NWs. Finally, multiple protein detection was demonstrated using a five-by-eight microfluidic channel array. Fluorescence images present clear multiple detections at the crossover areas when using the sharp ZnO NWs for simultaneous dye-conjugated anti-mouse IgG and dye-conjugated anti-rabbit IgG (Alexa 647) detection.
authors: Institute of Nanotechnology/Department of Materials Science and Engineering, National Chiao Tung University, 1001 Ta-Hsueh Road, Hsinchu 30050, Taiwan.
authors: Chen-Hsiang
authors: CH
authors: Sang
authors: Institute of Plant and Microbial Biology, Academia Sinica, Taipei 115, Taiwan.
authors: Shu-Jen
authors: SJ
authors: Chou
authors: Institute of Nanotechnology/Department of Materials Science and Engineering, National Chiao Tung University, 1001 Ta-Hsueh Road, Hsinchu 30050, Taiwan.
authors: F M
authors: FM
authors: Pan
authors: Institute of Boimedical Engineering, National Chiao Tung University, 1001 Ta-Hsueh Road, Hsinchu 30050, Taiwan. Electronic address: jtsheu@faculty.nctu.edu.tw.
authors: Jeng-Tzong
authors: JT
authors: Sheu
mesh_terms: D000818:Animals; D015374:Biosensing Techniques; D001710:Biotin / Q000737:chemistry; D005453:Fluorescence; D007074:Immunoglobulin G / Q000302:isolation & purification*; D056656:Lab-On-A-Chip Devices; D051379:Mice; D049329:Nanostructures; D053770:Nanowires / Q000737:chemistry*; D011817:Rabbits; D015034:Zinc Oxide / Q000737:chemistry
chemical_list: D007074:Immunoglobulin G; D001710:Biotin; D015034:Zinc Oxide
keywords: Fluorescence enhancement; Microfluidic channel; Multiple protein detection; ZnO nanostructures