Mulchandani Priti, Hangarter Carlos M, Lei Yu, Chen Wilfred, Mulchandani Ashok
Department of Chemical and Environmental Engineering, University of California, Riverside, CA 92521, USA.
Biosens Bioelectron. 2005 Sep 15;21(3):523-7. doi: 10.1016/j.bios.2004.11.011. Epub 2004 Dec 29.
An amperometric microbial biosensor for highly specific, sensitive and rapid quantitative determination of p-nitrophenol was developed. The biosensor takes advantage of the ability of Moraxella sp. to specifically degrade p-nitrophenol to hydroquinone, a more electroactive compound than p-nitrophenol. The electrochemical oxidation current of hydroquinone formed in biodegradation of p-nitrophenol was measured at Moraxella sp.-modified carbon paste electrode and correlated to p-phenol concentrations. The optimum response was realized by electrode constructed using 15 mg of dry cell weight per 1 g of carbon paste and operating at 0.3 V (versus Ag/AgCl reference) in pH 7.5, 20 mM sodium phosphate buffer. Operating at these optimum conditions the biosensor had excellent selectivity against phenol derivatives and was able to measure as low as 20 nM (2.78 ppb) p-nitrophenol with very good accuracy and reproducibility. The biosensor was stable for approximately 3 weeks when stored at 4 degrees C. The applicability of the biosensor to measure p-nitrophenol in lake water was demonstrated.
开发了一种用于高特异性、灵敏且快速定量测定对硝基苯酚的安培型微生物生物传感器。该生物传感器利用莫拉克斯氏菌属特异性地将对硝基苯酚降解为对苯二酚的能力，对苯二酚是一种比对硝基苯酚更具电活性的化合物。在莫拉克斯氏菌属修饰的碳糊电极上测量对硝基苯酚生物降解过程中形成的对苯二酚的电化学氧化电流，并将其与对硝基苯酚浓度相关联。通过使用每1克碳糊15毫克干细胞重量构建的电极，并在pH 7.5、20 mM磷酸钠缓冲液中于0.3 V（相对于Ag/AgCl参比电极）下操作，实现了最佳响应。在这些最佳条件下操作时，该生物传感器对对苯酚衍生物具有出色的选择性，能够以非常好的准确度和重现性测量低至20 nM（2.78 ppb）的对硝基苯酚。当储存在4℃时，该生物传感器稳定约3周。证明了该生物传感器在测量湖水中对硝基苯酚方面的适用性。
