Double-sided microfluidic device for speciation analysis of iron in water samples: Towards greener analytical chemistry

• Main Authors: Napaporn Youngvises, Porapichcha Thanurak, Thanatcha Chaida, Jaroon Jukmunee, Awadh Alsuhaimi
• Format: Journal
• Published: 2018
• Subjects: Agricultural and Biological Sciences
• Online Access: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84930329153&origin=inward; http://cmuir.cmu.ac.th/jspui/handle/6653943832/44820
• Institution: Chiang Mai University

© The Japan Society for Analytical Chemistry. 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.