Methylene blue-carbon nitride system as a reusable air-sensor
Por:
Dante R.C., Trakulmututa J., Meejoo-Smith S., Martín-Ramos P., Chamorro-Posada P., Rutto D., Sánchez-Arévalo F.M.
Publicada:
1 ene 2019
Resumen:
Methylene blue (MB)is a dye widely used as an optical redox indicator in analytical chemistry, whose color change is also affected by pH. It was irreversibly adsorbed on polymeric carbon nitride (g-C 3 N 4 )prepared either from urea or from melamine cyanurate. Electron spin resonance (ESR)showed an increase in radicals or unpaired electrons in the MB-g-C 3 N 4 system in comparison to pure g-C 3 N 4 . Upon treatment with potassium hydroxide, an abrupt color change from blue to purple occurred, together with a decrease in the ESR signal. Exposure to air caused a shift to the initial blue color, and, as suggested by UV-Vis spectroscopy data, the system returned to its original state, before the treatment with alkali. This behavior suggests the suitability of the MB-g-C 3 N 4 system as a promising reusable sensor for the detection of exposure to air (and/or to carbon dioxide)of products stored under vacuum or in a controlled atmosphere. Thus, visual indicators based on this material may find applications as cost-effective leakage indicators for the modified atmosphere package (MAPs)industry, in particular to assess food safety or for electronic packaging. © 2019 Elsevier B.V.
Filiaciones:
Dante R.C.:
Research, Development & Innovation, 2Dto3D S.r.l.s. Via Revalanca 5, San Firmino, Revello, CN 12036, Italy
Trakulmututa J.:
Department of Chemistry, Faculty of Science, Mahidol University, 999 Phuttamonthon Sai 4 Road, Salaya, Phuttamonthon, Nakhon Pathom, 73170, Thailand
Meejoo-Smith S.:
Department of Chemistry, Faculty of Science, Mahidol University, 999 Phuttamonthon Sai 4 Road, Salaya, Phuttamonthon, Nakhon Pathom, 73170, Thailand
Martín-Ramos P.:
EPS, Instituto de Investigación en Ciencias Ambientales (IUCA), Universidad de Zaragoza, Carretera de Cuarte s/n, Huesca, 22071, Spain
Chamorro-Posada P.:
Dpto. de Teoría de la Señal y Comunicaciones e IT, Universidad de Valladolid, ETSI Telecomunicación, Paseo Belén 15, Valladolid, 47011, Spain
Rutto D.:
R&D Department, Burgo Group, Via Roma 10, Verzuolo, CN 12039, Italy
Sánchez-Arévalo F.M.:
Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, Apdo. Postal 70-360, Cd. Universitaria, Mexico City, 04510, Mexico
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