Temperature and pH sensors based on graphenic materials.
Point-of-care applications and patients' real-time monitoring outside a clinical setting would require disposable and durable sensors to provide better therapies and quality of life for patients. This paper describes the fabrication and performances of a temperature and a pH sensor on a biocompatible and wearable board for healthcare applications. The temperature sensor was based on a reduced graphene oxide (rGO) layer that changed its electrical resistivity with the temperature. When tested in a human serum sample between 25 and 43°C, the sensor had a sensitivity of 110±10Ω/°C and an error of 0.4±0.1°C compared with the reference value set in a thermostatic bath. The pH sensor, based on a graphene oxide (GO) sensitive layer, had a sensitivity of 40±4mV/pH in the pH range between 4 and 10. Five sensor prototypes were tested in a human serum sample over one week and the maximum deviation of the average response from reference values obtained by a glass electrode was 0.2pH units. For biological applications, the temperature and pH sensors were successfully tested for in vitro cytotoxicity with human fibroblast cells (MRC-5) over 24h.
Institute of Clinical Physiology, National Council of Research (IFC-CNR), Via Moruzzi 1, 56124 Pisa, Italy; Department of Chemistry and Industrial Chemistry, University of Pisa, Via Moruzzi 13, 56124 Pisa, Italy.
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Salvo
Department of Chemistry and Industrial Chemistry, University of Pisa, Via Moruzzi 13, 56124 Pisa, Italy.
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Calisi
Department of Chemistry and Industrial Chemistry, University of Pisa, Via Moruzzi 13, 56124 Pisa, Italy.
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Melai
INSTM, National Interuniversity Consortium of Materials Science and Technology, Via G. Giusti 9, 50121 Firenze, Italy; Department of Chemistry "U. Schiff", University of Florence, Via della Lastruccia 3-13, 50019 Sesto Fiorentino (FI), Italy.
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Cortigiani
INSTM, National Interuniversity Consortium of Materials Science and Technology, Via G. Giusti 9, 50121 Firenze, Italy; Department of Chemistry "U. Schiff", University of Florence, Via della Lastruccia 3-13, 50019 Sesto Fiorentino (FI), Italy.
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Mannini
INSTM, National Interuniversity Consortium of Materials Science and Technology, Via G. Giusti 9, 50121 Firenze, Italy; Department of Chemistry "U. Schiff", University of Florence, Via della Lastruccia 3-13, 50019 Sesto Fiorentino (FI), Italy.
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Caneschi
Applied and Laser Spectroscopy Laboratory, ICCOM-CNR, Research Area of Pisa, Via G. Moruzzi 1, 56124 Pisa, Italy.
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Lorenzetti
Department of Chemistry and Industrial Chemistry, University of Pisa, Via Moruzzi 13, 56124 Pisa, Italy.
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Paoletti
Department of Chemistry and Industrial Chemistry, University of Pisa, Via Moruzzi 13, 56124 Pisa, Italy.
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Lomonaco
Department of Experimental Pathology, University of Pisa Medical School, Via Roma 55, Pisa 56126, Italy.
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Paolicchi
Department of Experimental Pathology, University of Pisa Medical School, Via Roma 55, Pisa 56126, Italy.
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Scataglini
Wound Healing Research Unit, Department of Dermatology, University of Pisa, Via Roma 67, 56126 Pisa, Italy.
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Dini
Wound Healing Research Unit, Department of Dermatology, University of Pisa, Via Roma 67, 56126 Pisa, Italy.
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Romanelli
Department of Chemistry and Industrial Chemistry, University of Pisa, Via Moruzzi 13, 56124 Pisa, Italy.
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Fuoco
Department of Chemistry and Industrial Chemistry, University of Pisa, Via Moruzzi 13, 56124 Pisa, Italy; INSTM, National Interuniversity Consortium of Materials Science and Technology, Via G. Giusti 9, 50121 Firenze, Italy. Electronic address: fabio.difrancesco@unipi.it.
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Di Francesco
D015374:Biosensing Techniques / Q000295:instrumentation*; D001774:Blood Chemical Analysis / Q000295:instrumentation*; D002460:Cell Line; D002470:Cell Survival; D004867:Equipment Design; D005347:Fibroblasts / Q000166:cytology; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008422:Materials Testing; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry; D013696:Temperature; D013821:Thermometers
D010087:Oxides; D006108:Graphite
Flexible sensor; Graphene; Temperature; pH