Porphyrinoids-Junctions Based Chemical Sensors
Authors: Magna Gabriele , Di Zazzo Lorena , Stefanelli Manuela , Catini Alexandro , Capuano Rosamaria , Paolesse Roberto , Di Natale Corrado 
Published: September 2023

The three main elements that form the porphyrinoids (aromatic ring, metal atom, and lateral compounds) provide the key to direct the chemical reactivity of the molecule towards desired classes of compounds. This property gives rise to a manifold of molecular architectures each with distinct features, that, in many cases, make them suitable for technological applications, among the others, chemical sensing.
The gas sensing properties of porphyrinoids involves the interaction with airborne molecules [1,2]. These are driven by a multiplicity of mechanisms including hydrogen bond, Van der Waals forces, and coordination that are active at once. Coordinating molecules, such as amines, have a preferential absorption onto porphyrins solid state layers, however the response to other molecules is not negligible so, eventually porphyrin sensors are seldom selective. However, the pattern of sensitivity strongly depends on slight changes in the molecular structure. This facilitate the development of sensor arrays that can easily implement the combinatorial selectivity principle of olfaction [3]. This property has been exploited to prepare electronic noses for various applications, not least medical diagnosis from the analysis of the volatile portion of the human metabolites [4–6].
These results were obtained coating with porphyrin layers the surface of quartz microbalance sensors. These are mass sensitive piezoelectric devices where the crystal resonance frequency is matched with the electric resonance. Mass sensors are quite suitable to prepare sensors that preserve the global sensitivity pattern of porphyrinoids, thus enabling an efficient combinatorial selectivity suitable for those applications which are characterized by patterns of volatile compounds. In spite of these positive properties, quartz microbalances are bulky and costly devices not suitable for low-costs, miniaturized devices. Thus, the current challenge is the development of impedance-based sensors that can preserve the wide sensitivity pattern of porphyrinoids.
To this regard, we have been interested to study the combination of porphyrnoids with conductive materials such as inorganic, and organic semiconductors.
In this presentation some relevant results will be present in particular about porphyrinoids coated ZnO nanostructures [7], the functionalization of the internal surface of face-masks with blends of porphyrinoids and PEDOT [8]and the heterojunctions formed by corrole polymer and phthalocyanine [9]. The sensitivity patterns of these devices approaches the behavior of quartz microbalance sensors paving the way for an effective large-scale deployment of porphyrinoids based artificial olfaction systems.
Reference
[1] R. Paolesse, Porphyrinoids for Chemical Sensor Applications, Chem. Rev. 117 (2017) 2517–2583.
[2] C. Di Natale, C.P. Gros, R. Paolesse, Corroles at work: a small macrocycle for great applications, Chem. Soc. Rev. 51 (2022) 1277–1335.
[3] I. Manzini, D. Schild, Di Natale C., Principles of odor coding in vertebrates and artificial chemosensory systems, Physiol. Rev. 102 (2022) 61–154.
[4] R. Gasparri, R. Capuano, A. Guaglio, V. Caminiti, F. Canini, A. Catini, G. Sedda, R. Paolesse, C. Di Natale, L. Spaggiari, Volatolomic urinary profile analysis for diagnosis of the early stage of lung cancer, J. Breath Res. 16 (2022).
[5] Y.K. Mougang, L. Di Zazzo, M. Minieri, R. Capuano, A. Catini, J.M. Legramante, R. Paolesse, S. Bernardini, C. Di Natale, Sensor array and gas chromatographic detection of the blood serum volatolomic signature of COVID-19, IScience. 24 (2021) 102851.
[6] M. Murdocca, F. Torino, S. Pucci, M. Costantini, R. Capuano, C. Greggi, C. Polidoro, G. Somma, V. Pasqualetti, Y. Ketchanji Mougang, A. Catini, G. Simone, R. Paolesse, A. Orlandi, A. Mauriello, M. Roselli, A. Magrini, G. Novelli, C. Di Natale, F.C. Sangiuolo, Urine LOX-1 and Volatilome as Promising Tools towards the Early Detection of Renal Cancer, Cancers (Basel). 13 (2021) 4213.
[7] G. Magna, M. Muduganti, M. Stefanelli, Y. Sivalingam, F. Zurlo, E. Di Bartolomeo, A. Catini, E. Martinelli, R. Paolesse, C. Di Natale, Light-Activated Porphyrinoid-Capped Nanoparticles for Gas Sensing, ACS Appl. Nano Mater. 4 (2021) 414–424.
[8] L. Di Zazzo, G. Magna, M. Lucentini, M. Stefanelli, R. Paolesse, C. Di Natale, Sensor-embedded face masks for detection of volatiles in breath: A proof of concept study, Chemosensors. 9 (2021).
[9] L. Di Zazzo, A. Kumar, R. Meunier-Prest, C. Di Natale, R. Paolesse, M. Bouvet, Electrosynthesized copper polycorroles as versatile materials in double lateral heterojunctions (submitted) 2022.