Affiliation:
1. Institute of Chemistry Masaryk University Kamenice 5 Brno 652 00 Czech Republic
2. Department of Chemistry University of Ioannina Ioannina 451 10 Greece
Abstract
AbstractSalivary thiocyanate is a biomarker of individual health that notably allows for the discrimination between smokers and non‐smokers. Recent studies have also demonstrated its potential as a biomarker of cystic fibrosis, thus rendering the development of methods for its determination in saliva of immense importance. In response, we report on the development of graphite screen‐printed electrodes (SPE) modified with cobalt(II) phthalocyanine nanosticks (CoPcNst), as low‐cost and semi‐disposable sensors for the determination of thiocyanate ion (SCN−) in human saliva. CoPCNst were synthesized and characterized using scanning electron microscopy, x‐ray diffraction, as well as infrared and Raman spectroscopies. The results revealed a structural proximity to the recently identified J‐polymorph. Compared with the electrode modified with commercial, beta‐structure cobalt(II) phthalocyanine, the CoPc Nst/SPE provided four times better LOD and LOQ (0.49 and 1.62 μM) for thiocyanate determination by differential pulse voltammetry. The response was linear up to 20 μM SCN− (R2=0.996) and it was not affected by excess of common electro active compounds, such as ascorbic and uric acid. The analytical utility of CoPc Nst/SPE in human saliva is demonstrated.