title: Double-sided Microfluidic Device for Speciation Analysis of Iron in Water Samples: Towards Greener Analytical Chemistry.
abstract: Microfluidics minimize the amounts of reagents and generate less waste. While microdevices are commonly single-sided, producing a substrate with microchannels on multiple surfaces would increase their usefulness. Herein, a polymethymethacrylate substrate incorporating microchannel structures on two sides was sandwiched between two polydimethylsiloxane sheets to create a multi-analysis device, which was used for the spectrophotometric analysis of the ferrous ion (Fe(2+)) and the ferric ion (Fe(3+)), by utilizing colorimetric detection. To monitor the signals from both channel networks, dual optical sensors were integrated into the system. The linear ranges for Fe(2+) and Fe(3+) analyses were 0.1 - 20 mg L(-1) (R(2) = 0.9988) and 1.0 - 40 mg L(-1) (R(2) = 0.9974), respectively. The detection limits for Fe(2+) and Fe(3+) were 0.1 and 0.5 mg L(-1), respectively. The percent recoveries of Fe(2+) and Fe(3+) were 93.5 - 104.3 with an RSD < 8%. The microdevice demonstrated capabilities for simultaneous analysis, low waste generation (7.2 mL h(-1)), and high sample throughput (180 h(-1)), making it ideal for greener analytical chemistry applications.
authors.affiliation: Innovative Green Chemistry Research Unit, Department of Chemistry, Faculty of Science and Technology, Thammasat University.
authors.forename: Napaporn
authors.initials: N
authors.lastname: Youngvises
authors.forename: Porapichcha
authors.initials: P
authors.lastname: Thanurak
authors.forename: Thanatcha
authors.initials: T
authors.lastname: Chaida
authors.forename: Jaroon
authors.initials: J
authors.lastname: Jukmunee
authors.forename: Awadh
authors.initials: A
authors.lastname: Alsuhaimi