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Electro-actuated polymer (EAP) can change its shape or volume under the action of an external electric field and shows similar behavioral characteristics with those of biological muscles, and so it has good application prospects in aerospace, bionic robots, and other fields. The properties of cellulose-based electroactive materials are similar to ionic EAP materials, although they have higher Young's modulus and lower energy consumption. However, cellulose-based electroactive materials have a more obvious deficiency-their actuation performance is often more significantly affected by ambient humidity due to the hygroscopicity caused by the strong hydrophilic structure of cellulose itself. Compared with cellulose, chitosan has good film-forming and water retention properties, and its compatibility with cellulose is very excellent. In this study, a chitosan/cellulose composite film doped with ionic liquid, 1-ethyl-3-methylimidazolium acetate ([EMIM]Ac), was prepared by co-dissolution and regeneration process using [EMIM]Ac as the solvent. After that, a conductive polymer, poly(3,4-ethylenedioxythiophene)/poly (styrene sulfonate) (PEDOT: PSS), was deposited on the surface of the resulted composite, and then a kind of cellulose-based electroactive composites were obtained. The results showed that the end bending deformation amplitude of the resulted material was increased by 2.3 times higher than that of the pure cellulose film under the same conditions, and the maximum deformation amplitude reached 7.3 mm. The tensile strength of the chitosan/cellulose composite film was 53.68% higher than that of the cellulose film, and the Young's modulus was increased by 72.52%. Furthermore, in comparison with the pure cellulose film, the water retention of the composite film increased and the water absorption rate decreased obviously, which meant that the resistance of the material to changes in environmental humidity was greatly improved.

Water-miscible alkylimidazolium ionic liquids (ILs) are "green" co-solvents for laccase catalysis, but generally inhibit enzyme activity. Here, we present novel insights into inhibition mechanisms by a combination of enzyme kinetics analysis and molecular simulation. Alkylimidazolium cations competitively bound to the T I Cu active pocket in the laccase through hydrophobic interactions. Cations with shorter alkyl chains (C₂~C₆) entered the channel inside the pocket, exhibiting a high compatibility with laccase (competitive inhibition constant K ic = 3.36~3.83 mM). Under the same conditions, [Omim]Cl (K ic = 2.15 mM) and [Dmim]Cl (K ic = 0.18 mM) with longer alkyl chains bound with Leu296 or Leu297 near the pocket edge and Leu429 around T I Cu, which resulted in stronger inhibition. Complexation with alkylimidazolium cations shifted the pH optima of laccase to the right by 0.5 unit, and might, thereby, lead to invalidation of the Hofmeister series of anions. EtSO₄ - showed higher biocompatibility than did Ac - or Cl - , probably due to its binding near the T I Cu and its hindering the entry of alkylimidazolium cations. In addition, all tested ILs accelerated the scavenging of 2, 2'-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radicals, which, however, did not play a determining role in the inhibition of laccase., Competing Interests: The authors declare no conflict of interest. The founding sponsors had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, and in the decision to publish the results.

During the manufacturing of pharmaceutical compounds, solvent mixtures are commonly used, where the addition of a cosolvent allows for the tuning of the intermolecular interactions present in the system. Here we demonstrate how a similar effect can be accomplished using a room temperature ionic liquid. The pharmaceutical compound acetaminophen is studied in 21 common ionic liquids composed of a 1-n-alkyl-3-methylimidazolium cation with 1 of 7 anions. Using the acetate anion, we predict a large enhancement in solubility of acetaminophen relative to water. We show how this is caused by a synergistic effect of favorable interactions between the ionic liquid and the phenyl, hydroxyl and amide groups of acetaminophen, demonstrating how the ionic liquid cation and anion may be chosen to preferentially solvate different functional groups of complex pharmaceutical compounds. Additionally, while the use of charge scaling in ionic liquid force fields has previously been found to have a minute effect on ionic liquid structural properties, we find it appreciably affects the computed solvation free energy of acetaminophen, which in turn affects the predicted solubility.

2-Methylimidazole (2-MI) and 4-methylimidazole (4-MI) can be formed via the Maillard reaction during dairy thermal treatment. In this study, different reactions between α-dicarbonyl compounds (methylglyoxal, glyoxal) and aldehydes (formaldehyde, acetaldehyde) in the presence of ammonium sulfate were performed to investigate the formation of 2-MI and 4-MI. Two formation pathways of 2-MI and 4-MI were proposed. One pathway is that α-dicarbonyl compound reacts with equivalent ammonia to form an intermediate, while aldehyde reacts with equivalent ammonia to form another intermediate, then the 2 intermediates react together to generate 2-MI or 4-MI. Alternatively, α-dicarbonyl compound can react with double ammonia to form an intermediate, and subsequently reacts with aldehyde to form 2-MI or 4-MI. Additionally, possible mechanisms were also proposed to explain the phenomenon that the 2-MI content was much lower than 4-MI in Maillard reaction., (Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

A simultaneous analysis of methylimidazoles, reducing sugars, and 5-hydroxymethyl-2-furaldehyde in the Maillard reaction was improved by use of an amino trap column. Analysis was carried out by using high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) coupled with an amino trap column. The amino trap column was a useful tool to improve the separation of methylimidazoles, reducing sugars, and 5-hydroxymethyl-2-furaldehyde. This technique is useful for simultaneous analysis of methylimidazoles, reducing sugars, and 5-hydroxymethyl-2-furaldehyde in risk assessment for dairy products., (Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)