A rapid and sensitive method for hydroxyl radical detection on a microfluidic chip using an N-doped porous carbon nanofiber modified pencil graphite electrode.
Hydroxyl radicals (˙OH) play an important role in human diseases. Traditional detection methods are time consuming and require expensive instruments. Here, we present a simple and sensitive method for the detection of hydroxyl radicals on a microfluidic chip using an electrochemical technique. Aniline monomer is electrochemically polymerized on the surface of a pencil graphite electrode and carbonized at 800 °C. The resulting N-doped porous carbon nanofiber-modified pencil graphite electrode is embedded into a microfluidic chip directly as a working electrode. 4-Hydroxybenzoic acid (4-HBA) is selected as the trapping agent owing to its unique 3,4-DHBA product and high trapping efficiency. A low detection limit of 1.0 × 10(-6) M is achieved on the microfluidic chip. As a demonstration, the microfluidic chip is successfully utilized for the detection of ˙OH in cigarette smoke. The strong π-π stacking and hydrophobic interactions between the nitrogen-doped carbon materials and the pencil graphite make the modified electrode well-suited for the microfluidic chip.
State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, China. xhxia@nju.edu.cn.
Jun
J
Ouyang
Zhong-Qiu
ZQ
Li
Jing
J
Zhang
Chen
C
Wang
Jiong
J
Wang
Xing-Hua
XH
Xia
Guo-Jun
GJ
Zhou
D002244:Carbon / Q000737:chemistry; D055664:Electrochemical Techniques / Q000191:economics / Q000295:instrumentation*; D004867:Equipment Design; D006108:Graphite / Q000737:chemistry*; D017665:Hydroxyl Radical / Q000032:analysis*; D057230:Limit of Detection; D046210:Microfluidic Analytical Techniques / Q000191:economics / Q000295:instrumentation*; D057139:Nanofibers / Q000737:chemistry* / Q000648:ultrastructure; D010226:Parabens / Q000737:chemistry; D016062:Porosity; D012906:Smoke / Q000032:analysis; D014026:Nicotiana / Q000737:chemistry
D010226:Parabens; D012906:Smoke; D017665:Hydroxyl Radical; D002244:Carbon; D006108:Graphite; C038193:4-hydroxybenzoic acid