title: Highly pH-responsive sensor based on amplified spontaneous emission coupled to colorimetry.
abstract: We demonstrated a simple, directly-readable approach for high resolution pH sensing. The method was based on sharp changes in Amplified Spontaneous Emission (ASE) of a Stilbene 420 (ST) laser dye triggered by the pH-dependent absorption of Bromocresol Green (BG). The ASE threshold of BG:ST solution mixtures exhibited a strong dependence on BG absorption, which was drastically changed by the variations of the pH of BG solution. As a result, ASE on-off or off-on was observed with different pH levels achieved by ammonia doping. By changing the concentration of the BG solution and the BG:ST blend ratio, this approach allowed to detect pH changes with a sensitivity down to 0.05 in the 10-11 pH range.
authors.affiliation: Key Laboratory for Organic Electronics and Information Displays &Institute of Advanced Materials, National Jiangsu Synergistic Innovation Center for Advanced Materials (SICAM), Nanjing University of Posts and Telecommunications, 9 Wenyuan Road, Nanjing 210046, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Madrid Institute for Advanced Studies, IMDEA Nanociencia, Calle Faraday 9, Ciudad Universitaria de Cantoblanco, 28049, Spain.
authors.forename: Jose R
authors.initials: JR
authors.lastname: Castro Smirnov
authors.affiliation: Key Laboratory for Organic Electronics and Information Displays &Institute of Advanced Materials, National Jiangsu Synergistic Innovation Center for Advanced Materials (SICAM), Nanjing University of Posts and Telecommunications, 9 Wenyuan Road, Nanjing 210046, China.
authors.forename: Ruidong
authors.initials: R
authors.lastname: Xia
authors.affiliation: Department of Physical, Chemical and Natural System, Universidad Pablo de Olavide, Seville, ES 41013, Spain.
authors.forename: Jose M
authors.initials: JM
authors.lastname: Pedrosa
authors.affiliation: Madrid Institute for Advanced Studies, IMDEA Nanociencia, Calle Faraday 9, Ciudad Universitaria de Cantoblanco, 28049, Spain.
authors.forename: Isabel
authors.initials: I
authors.lastname: Rodriguez
authors.affiliation: Madrid Institute for Advanced Studies, IMDEA Nanociencia, Calle Faraday 9, Ciudad Universitaria de Cantoblanco, 28049, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Cabanillas-Gonzalez
authors.affiliation: Institute of Advanced Materials (IAM), Jiangsu-Singapore Joint Research Center for Organic/Bio-Electronics &Information Displays, Nanjing Tech University, 30 South Puzhu Road, Nanjing 211816, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Huang