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Ultrasmooth gold/silver/gold trilayer nanostructured plasmonic sensors were obtained using commercial Blu-ray optical discs as nanoslits-based flexible polymer substrates. A thin gold film was used as an adhesion and nucleation layer to improve the chemical stability and reduce the surface roughness of the overlying silver film, without increasing ohmic plasmon losses. The structures were physically and optically characterized and compared with nanostructures of single gold layer. Ultrasmooth and chemically stable trilayer nanostructures with a surface roughness, Departament d'Universitats, Recerca i Societat de la Informació, Grant/Award Number: 2014 SGR 624; Ministerio de Economía y Competitividad, Grant/Award Number: SEV-2013-0295; Programa Estatal de investigación, desarrollo e innovación orientada a los Retos de la Sociedad, Grant/Award Number: TEC2016-78515-R; Spanish Ministry of Economy, Industry and Competitiveness (MINECO, Grant/Award Number: SEV2013-0295; CERCA programme/Generalitat de Catalunya; Departament d'Universitats, Recerca i Societat de la Informació de la Generalitat de Catalunya, Grant/Award Number: 2014 SGR 624; PreDICT project, Grant/Award Number: TEC2016-78515-R; CONACYT, Grant/Award Number: 225362

A boron trifluoride–methanol complex demonstrated remarkable deprotection selectivity against commonly used amino-protecting groups in the deacetylation of acetanilides and high sensitivity to the steric hindrance of substrates. The scope and limitations of the reaction were explored.

The construction and evaluation of a Low Temperature Co-fired Ceramics (LTCC)-based microsystem prototype as a possible on-site microanalyzer to monitor the presence of two ions in water simultaneously is presented. The approach has been assayed to detect nitrate and chloride ions as model analytes by means of integrating in the same single substrate an ion selective polymeric membrane to nitrate and two screen-printed Ag/AgCl electrodes. One supplies the chloride ion concentration and the other is to complete the potentiometric detection system as the reference electrode. The results obtained by the full characterization of the microanalyzer prove the relevance of the proposal and the possibility to be transferred to real-world samples and environmental monitoring.

A simulation procedure for the optimization of enzymatic reactors used in sandwich flow injection systems is evaluated. The system is modeled as a plug-flow reactor with axial dispersion. To calibrate it, dispersion coefficients can be evaluated using residence time distribution techniques; meanwhile, enzymatic kinetics must be determined for the system considered, according to the values of the substrate conversion attained. The model has been linked to an optimization routine based on the Powell algorithm. The proposed approach has been evaluated in a system performing simultaneous determinations of glucose and glycerol, considered the common carbon sources in a fermentation process.

Synthesis of new acidochromic-based dyes is presented. The dyes obtained have acid absorbance maxima at 640–700 nm and expose spectral changes in the pH-range from 8 to 12.

New one-step synthesis of ketocyanine dyes is presented. The dyes obtained expose spectral changes in pH range from 1.7 to 4.3 and their protonated forms absorb at 715–750 nm.

Novel nitrate-sensitive membranes have been developed using an aliphatic urethane diacrylate photocurable polymer. This polymer has been chosen due to its easy and fast deposition procedure compared with PVC membranes and its compatibility with microelectronic techniques. These membranes were obtained after UV irradiation during no more than 60 seconds. To optimize their composition and evaluate the chemical response ion selective electrodes (ISEs) with solid inner reference were used. Studies of different plasticizers for nitrate PVC membranes and compositions increasing the ratio between oligomer and diluting agent were performed. ISEs developed presented a sensitivity of −56 mV/dec and a lifetime up to one year. Membrane compositions containing dibutyl phthalate and trioctyl phosphate as plasticizers were deposited onto ISFETs. Studies to elongate ISFETs lifetime were carried out modifying the encapsulation methodology, by using the same polymer family. ISFETs showed a sensitivity between 65–69 mV/decade, depending on the plasticizer, and a linear range of 2.4×10−5−0.06 M. The long-term stability of ISFET sensors with trioctyl phosphate plasticizer was up to 10 months, being superior to that described in the literature for PVC membranes and even for other kind of polymers.