{"references": ["Kim R. Rogers, and Llewellyn R. Williams, \"Biosensors for\nenvironmental monitoring: a regulatory perspective,\" TrAC Trends in\nAnalytical Chemistry, vol. 14, n. 7, pp. 289-294, 1995", "J. W. Grate and M. H. Abraham, \"Solubility interaction and design of\nchemically selective sorbent coatings for chemical sensor and arrays,\"\nSens. Actuators B, Chem., vol. 3, no. 2, pp. 85-111, Feb 1991.", "M. Penza, G. Cassano, P. Aversa, F. Antolini, A. Cusano, M. Consales,\nM. Giordano, and L. Nicolais, \"Carbon nanotubes coated\nmultitransducing sensors for VOCs detection,\" Sens. Actuators B,\nChem., vol. 111/112, pp. 171-180, Nov. 11, 2005.", "M. Giordano, M. Russo, A. Cusano, G. Mensitieri, and G. Guerra,\n\"Syndiotactic polystyrene thin film as sensitive layer for an\noptoelectronic chemical sensing device,\" Sens. Actuators B, Chem., vol.\n109, no. 2, pp. 177-184, Sep. 2005.", "M. Giordano, M. Russo, A. Cusano, A. Cutolo, G. Mensitieri, and L.\nNicolais, \"Optical sensor based on ultrathin films of \u256c\u2524-form syndiotactic\npolystyrene for fast and high resolution detection of chloroform,\" Appl.\nPhys. Lett., vol. 85, no. 22, pp. 5349-5351, Nov 2004.", "A. Cusano, P. Pilla, L. Contessa, A. Iadicicco, S. Campopiano, A.\nCutolo, M. Giordano, \"High Sensitivity Optical Chemo-Sensor Based on\nCoated Long Period Gratings for Sub ppm Chemical Detection in\nWater\", Applied Physic Letters, vol. 87, 234105, December 2005.", "S. H. Lim, ,L. Feng, J. W. Kemling,, C. J. Musto,and K. S. Suslick, \"An\nOptoelectronic Nose for Detection of Toxic Gases,\"\nNature Chemistry, vol. 1, pp. 562-567, 2009", "Giovanna De Luca, Gianmichele Pollicino, Andrea Romeo, and Luigi\nMons\u251c\u2563 Scolaro, \"Sensing Behavior of Tetrakis(4-\nsulfonatophenyl)porphyrin Thin Films,\" Chem. Mater., vol. 18 no. 8, pp.\n2005-2007, 2006.", "MO. Senge, M. Fazekas, EGA. Notaras, WJ. Blau, M. Zawadzka, and\nOB. Locos, and EM. Ni Mhuircheartaigh, \"Nonlinear Optical Properties\nof Porphyrins\", Advanced Materials, vol. 19, pp. 2737-2774, Oct 2007\n[10] K. M. Kadish, K. M. Smith, R. Eds, Guilard, The Porphyrin Handbook.\nNew York: Academic Press, 2000, vol. 6\n[11] Koiti Araki, Michael J. Wagner, and Mark S. Wrighton, \"Layer-by-\nLayer Growth of Electrostatically Assembled Multilayer Porphyrin\nFilms,\" Langmuir, vol. 12, pp. 5393-5398, 1996.\n[12] Zhijun Zhang, Ruisheng Hu, and Zhongfan Liu, \"Formation of a\nPorphyrin Monolayer Film by Axial Ligation of Protoporphyrin IX Zinc\nto an Amino-Terminated Silanized Glass surface\", Langmuir, vol. 16,\npp. 537, 2000.\n[13] Luigi Mons\u251c\u2563 Scolaro,Andrea Romeo, Maria Angela\nCastriciano,Giovanna De Luca, Salvatore Patan\u00e8, and Norberto Micali,\n\"Porphyrin Deposition Induced by UV Irradiation,\" J. Am. Chem. Soc.,\nvol. 125 (8), pp. 2040-2041, 2003\n[14] Xiao-Bing Zhanga, Zhi-Zhang Lib, Can-Cheng Guoa, Si-Hai Chena,\nGuo-Li Shena, and Ru-Qin Yua, \"Porphyrin-metalloporphyrin\ncomposite based optical fiber sensor for the determination of\nberberine,\", Analytica Chimica Acta, vol. 439, pp. 65-71, July 2001.\n[15] Rong Ni, Rong-Biao Tong, Can-Cheng Guo, Guo-Li Shen, Ru-Qin Yu,\n\"An anthracene/porphyrin dimer fluorescence energy transfer sensing\nsystem for picric acid,\" Talanta, vol. 63, pp. 251-257, May 2004.\n[16] George Huyang, John Canning, Mattias L. \u00c5slund, Danial Stocks, Tony\nKhoury, and Maxwell J. Crossley , \"Evaluation of optical fiber microcell\nreactor for use in remote acid sensing,\" Optics Letters, vol. 35, pp. 817-\n819, 2010\n[17] Selyanchyn, Roman, Korposh Sergiy, Yasukochi Wataru, and Lee\nSeung-Woo, \"A preliminary test for skin gas assessment using a\nporphyrin based evanescent wave optical fiber Sensor,\" Sensors &\nTransducers, vol. 125, no. 2, pp.54-67, Feb 2011.\n[18] A. P. H. J. Schenning, F. B. G. Benneker, H. P. M. Geurts, X. Y. Liu,\nand R. J. M. Nolte, \"Porphyrin Wheels,\" J. Am. Chem. Soc., vol. 118,\nno. 36, pp. 8549, 1996.\n[19] Giovanna De Luca,Giamichele Pollincino,Andrea Romeo,Salvatore\nPatane, and Luigi Monsu Scolaro, \"Control over the Optical and\nMorphological Properties of UV-Deposited Porphyrin Structures,\"\nChem. Mater, vol. 18, pp. 5429, 2006.\n[20] RF. Pasternack, and PJ. Collings, \"Resonance light scattering: a new\ntechnique for studying chromophore aggregation,\" Science, vol. 269, no.\n5226, pp. 935-935, 1995"]}

In this work we report on preliminary analysis of a novel optoelectronic gas sensor based on an optical fiber integrated with a tetrakis(4-sulfonatophenyl)porphyrin (TPPS) thin film. The sensitive materials are selectively deposited on the core region of a fiber tip by UV light induced deposition technique. A simple and cheap process which can be easily extended to different porphyrin derivatives. When the TPPS film on the fiber tip is exposed to acid and/or base vapors, dramatic changes occur in the aggregation structure of the dye molecules in the film, from J- to H-type, resulting in a profound modification of their corresponding reflectance spectra. From the achieved experimental results it is evident that the presence of intense and narrow band peaks in the reflected spectra could be monitored to detect hazardous vapors.