title: AAO-CNTs electrode on microfluidic flow injection system for rapid iodide sensing.
abstract: In this work, carbon nanotubes (CNTs) nanoarrays in anodized aluminum oxide (AAO-CNTs) nanopore is integrated on a microfluidic flow injection system for in-channel electrochemical detection of iodide. The device was fabricated from PDMS (polydimethylsiloxane) microchannel bonded on glass substrates that contains three-electrode electrochemical system, including AAO-CNTs as a working electrode, silver as a reference electrode and platinum as an auxiliary electrode. Aluminum, stainless steel catalyst, silver and platinum layers were sputtered on the glass substrate through shadow masks. Aluminum layer was then anodized by two-step anodization process to form nanopore template. CNTs were then grown in AAO template by thermal chemical vapor deposition. The amperometric detection of iodide was performed in 500-μm-wide and 100-μm-deep microchannels on the microfluidic chip. The influences of flow rate, injection volume and detection potential on the current response were optimized. From experimental results, AAO-CNTs electrode on chip offers higher sensitivity and wider dynamic range than CNTs electrode with no AAO template.
authors.affiliation: Nanoelectronics and MEMS Laboratory, National Electronics and Computer Technology Center, Pathumthani 12120, Thailand.
authors.forename: Ditsayut
authors.initials: D
authors.lastname: Phokharatkul
authors.forename: Chanpen
authors.initials: C
authors.lastname: Karuwan
authors.forename: Tanom
authors.initials: T
authors.lastname: Lomas
authors.forename: Duangjai
authors.initials: D
authors.lastname: Nacapricha
authors.forename: Anurat
authors.initials: A
authors.lastname: Wisitsoraat
authors.forename: Adisorn
authors.initials: A
authors.lastname: Tuantranont
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry*; D004129:Dimethylpolysiloxanes / Q000737:chemistry; D004566:Electrodes; D017022:Flow Injection Analysis / Q000295:instrumentation*; D005898:Glass / Q000737:chemistry; D007202:Indicators and Reagents / Q000737:chemistry; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D011193:Potassium Iodide / Q000032:analysis* / Q000737:chemistry; D013997:Time Factors; D014835:Volatilization
chemical_list: D004129:Dimethylpolysiloxanes; D007202:Indicators and Reagents; D037742:Nanotubes, Carbon; D011193:Potassium Iodide; C013830:baysilon; D000537:Aluminum Oxide