Sensitive electrochemical detection of sodium azide based on the electrocatalytic activity of the pasting liquid of a carbon paste electrode
Sodium azide (NaN3) is highly toxic and widely used in, for example, automobile airbags and biochemical laboratories. The electrochemical detection of sodium azide on commonly used electrodes is challenging due to sluggish electron transfer, but it has been achieved using a boron-doped diamond thin-film electrode and a highly oriented pyrolytic graphite electrode. Utilizing the electrocatalytic activity of the pasting liquid of a carbon paste electrode, we developed an effective method for the electrochemical detection of sodium azide in which silicone oil was employed as the pasting liquid of the carbon paste electrode. This simple and cheap silicone-oil-based carbon paste electrode exhibited comparable sensitivity to the boron-doped diamond thin-film electrode and highly oriented pyrolytic graphite electrode. The limit of detection for sodium azide at the silicone-oil-based carbon paste electrode was found to be 0.1 μM. Recoveries from diluted human serum samples were between 97.2 and 101.3%.
KeywordsSodium azide Pasting liquid Electrocatalysis Carbon paste electrode Detection
Financial support from the National Natural Science Foundation of China (nos. 21675148 and 21505128), the Natural Science Foundation of Guangxi Province of China (project no. 2015GXNSFFA139005), the National Key Research and Development Program of China (no. 2016YFA0201300), and the CAS-TWAS (Academy of Sciences for the Developing World) President’s Fellowship for International PhD Students is appreciated.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
- 10.Wang K, Friscourt F, Dai C, Wang L, Zheng Y, Boons GJ, et al. A metal-free turn-on fluorescent probe for the fast and sensitive detection of inorganic azides. Bioorg Med Chem Lett. 2016;26(7):1651–4.Google Scholar
- 12.Suzuki A, Ivandini TA, Kamiya A, Nomura S, Yamanuki M, Matsumoto K, et al. Direct electrochemical detection of sodium azide in physiological saline buffers using highly boron-doped diamond electrodes. Sensor Actuators B Chem. 2007;120(2):500–7.Google Scholar
- 14.Svancara I, Walcarius A, Kalcher K, Vytras K. Carbon paste electrodes in the new millennium. Cent Eur J Chem. 2009;7(4):598–656.Google Scholar
- 16.Adams RN. Carbon paste electrodes. Anal Chem. 1958;30(9):1576–6.Google Scholar
- 18.Bard AJ, Faulkner LR. Electrochemical methods: fundamentals and applications. 2nd ed. New York: Wiley; 2001.Google Scholar