Nitrite Biosensing Using Cytochrome C Nitrite Reductase: Towards a Disposable Strip Electrode - Biomedical Engineering Systems and Technologies - page 28

interference level (+3%) was not significant. In contrast, the interference caused by
hydroxylamine, an alternative ccNiR substrate, was about 10%; although much lower
than the values obtained with some other electrode configurations [10-15], it can not
be neglected. Though, the risks of having both species in the same physiological
sample are not great.

4 Conclusions

This R&D project was designed to address a critical and growing need for real-time
monitoring of nitrites and to provide better analytical tools for its clinical diagnosis.
Our previous results have demonstrated the feasibility of using ccNiR in the
construction of bioelectrodes for a selective nitrite analysis [10-15]. Herein we have
shown the biocompatibility of the painting materials and the electrode curing
procedure with ccNiR activity. The success of this work opens up the possibility of
including the enzyme directly in the printing paste used for the fabrication of thick-
film electrodes, facilitating the mass production of easy-to-use nitrite biosensors. If
coupled to a portable potentiostat, these enzyme containing disposable electrode strips
will turn a long and elaborated laboratory protocol into a simple task, quickly
executed onsite.

Acknowledgements. The authors thank the financial support from Associated Labor-
atory REQUIMTE.

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