Ultrasensitive electrochemical detection of H2O2 in living cells based on ultrathin MnO2 nanosheets

• Published in: Sensors and actuators. B, Chemical Chemical, 2017-11, Vol.252, p.72-78
• Main Authors: Shu, Yun, Xu, Jing, Chen, Jingyuan, Xu, Qin, Xiao, Xiao, Jin, Dangqin, Pang, Huan, Hu, Xiaoya
• Format: Article
• Language: English
• Subjects: Electrocatalytic activity; Hydrogen peroxide; Living cells; MnO2 nanosheets; Nonenzymatic electrochemical sensor
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2017.05.124

•Two-dimensional ultrathin MnO2 nanosheets were synthesized using a facile and efficient method.•An ultrasensitive H2O2 nonenzymatic electrochemical sensor was constructed based on the ultrathin MnO2 nanosheets.•The constructed sensor was applied to perform real-time monitoring trace concentration of H2O2 released by living cells with satisfactory results. Using a facile and efficient method, two-dimensional (2D) ultra-thin MnO2 nanosheets were successfully prepared. Due to the large specific surface area and mesoporous structure, MnO2 nanosheet is a good candidate for use as an enhanced electrochemical sensing material. MnO2 nanosheets were immobilized onto glassy carbon electrodes with Nafion film to construct a H2O2 electrochemical nonenzymatic sensor. Amperometric study showed MnO2 nanosheets exhibited very high electrocatalytic activity towards H2O2 reduction. A very low detection limit (5nM) was reached with a wide linear range (25nM–2μM and 10–454μM) and a high sensitivity of 3261 mAM−1cm−2. The fabricated H2O2 sensor also exhibited excellent selectivity, good reproducibility and long-time stability. Furthermore, the constructed high sensitive sensor was successfully applied to perform real-time monitoring trace concentration of H2O2 released by SP2/0 cells, indicating that MnO2 nanosheets provide a new platform for developing high performance electrochemical sensors in biological applications.