Inhibition-based biosensor for cyanide detection – a preliminary study
Autor: | Ana R. Coelho, Tiago Monteiro, Ana S. Viana, M. Gabriela Almeida |
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Jazyk: | angličtina |
Rok vydání: | 2021 |
Předmět: | |
Zdroj: | Annals of Medicine, Vol 53, Iss sup1, Pp S41-S42 (2021) |
Druh dokumentu: | article |
ISSN: | 07853890 1365-2060 0785-3890 |
DOI: | 10.1080/07853890.2021.1896915 |
Popis: | AbstractIntroduction The acute toxicity of cyanide along with its continue industrial use makes this substance of environmental concern [1]. Titration, spectrophotometry and ISE are the standard detection methods. However, they are complex and need sample pre-treatment [2]. To overcome these, another approach is using biosensors. To this end, we developed a disposable inhibition-based biosensor with a multi-heme nitrite reductase (ccNiR) coupled to graphite leads.Materials and methods Electrochemical measurements were carried out in a conventional electrochemical cell, composed by a three-electrode system. The reference was an Ag/AgCl electrode, and the counter electrode was a Pt wire. The working electrode (WE) was in-house made using a graphite lead with the ccNiR (from bacteria D. desulfuricans ATCC 27774; stored in 0.05 M phosphate buffer, pH 7.6) immobilised by drop cast at the WE surface. The electrochemical technique used was square wave voltammetry. Electrochemical cells contained 0.1 M KCl in 0.1 M Tris–HCl buffer (pH 7.6) as supporting electrolyte. Dissolved oxygen was removed by a biochemical system (GOx, catalase and glucose).Discussion and conclusions In Figure 1 we can observe the decrease in catalytic activity due to the presence of cyanide. The biosensor dynamic range comprises the maximum value imposed by the European Union, 1.92 µM (98/83/EC directive), which does not happen with other cyanide biosensors [3]. Furthermore, a graphite lead cost 0.35€ and each of them can be split, allowing a very low-cost biosensor. Given that enzyme inhibition is reversible [4], the sensor can be used more than one time, if we optimise the enzyme immobilisation method.[Figure: see text] |
Databáze: | Directory of Open Access Journals |
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