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In this work, we demonstrate the solution processing of optical and electrochemical dye sensors based on 4-(dioctylamino)-4 0 -(trifluoroacetyl)azobenzene and its application in sensing different amine compounds.Distinct optical response of the sensors exposed to ammonia, tetramethylammonium hydroxide, ethylamine, cadaverine and putrescine (typical compounds upon the decomposition of proteins) is observed. Incorporation of inkjet deposited thin films of the dye as sensors in food packages of ground meat and salmon is found as a feasible route to detect the appearance of biogenic amines produced by the degrading food products. Furthermore, we demonstrate an electrochemical amine sensor based on (trifluoroacetyl)azobenzene dye added in carbon nanotube-Nafion® composites. The electrochemical sensor exploits the reaction between the dye and amines to detect amines in electrolytes, while the carbon nanotubes provide large surface for adsorption and also provide a percolating electrical network for allowing efficient charge transfer at the electrode electrolyte interface. Scheme 1 Bonding reaction of 4-(dioctylamino)-4 0 -(trifluoroacetyl)azobenzene and amine. 4688 | J. Mater. Chem. A, 2015, 3, 4687-4694 This journal is

Various di-and mono-substituted quinazolinones were synthesized by one-pot condensation of isatoic anhydride, aldehyde and amine, or ammonium carbonate using [bmim]HSO 4 as catalyst in aqueous medium. Water as a reaction media, recyclability of catalyst, shorter reaction time, and good yields (70Á90%) are some of the salient features of the developed protocol.

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BackgroundPretreatment is a vital step upon biochemical conversion of lignocellulose materials into biofuels. An acid catalyzed thermochemical treatment is the most commonly employed method for this purpose. Alternatively, ionic liquids (ILs), a class of neoteric solvents, provide unique opportunities as solvents for the pretreatment of a wide range of lignocellulose materials. In the present study, four ionic liquid solvents (ILs), two switchable ILs (SILs) DBU–MEA–SO2 and DBU–MEA–CO2, as well as two ‘classical’ ILs [Amim][HCO2] and [AMMorp][OAc], were applied in the pretreatment of five different lignocellulosic materials: Spruce (Picea abies) wood, Pine (Pinus sylvestris) stem wood, Birch (Betula pendula) wood, Reed canary grass (RCG, Phalaris arundinacea), and Pine bark. Pure cellulosic substrate, Avicel, was also included in the study. The investigations were carried out in comparison to acid pretreatments. The efficiency of different pretreatments was then evaluated in terms of sugar release and ethanol fermentation.ResultsExcellent glucan-to-glucose conversion levels (between 75 and 97 %, depending on the biomass and pretreatment process applied) were obtained after the enzymatic hydrolysis of IL-treated substrates. This corresponded between 13 and 77 % for the combined acid treatment and enzymatic hydrolysis. With the exception of 77 % for pine bark, the glucan conversions for the non-treated lignocelluloses were much lower. Upon enzymatic hydrolysis of IL-treated lignocelluloses, a maximum of 92 % hemicelluloses were also released. As expected, the ethanol production upon fermentation of hydrolysates reflected their sugar concentrations, respectively.ConclusionsUtilization of various ILs as pretreatment solvents for different lignocelluloses was explored. SIL DBU–MEA–SO2 was found to be superior solvent for the pretreatment of lignocelluloses, especially in case of softwood substrates (i.e., spruce and pine). In case of birch and RCG, the hydrolysis efficiency of the SIL DBU–MEA–CO2 was similar or even better than that of DBU–MEA–SO2. Further, the IL [AMMorp][OAc] was found as comparably efficient as DBU–MEA–CO2. Pine bark was highly amorphous and none of the pretreatments applied resulted in clear benefits to improve the product yields.Electronic supplementary materialThe online version of this article (doi:10.1186/s13068-015-0310-3) contains supplementary material, which is available to authorized users.