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The antibiotics residual presence in honey is a current problem with negative implications, mainly commercial since according to European legislation antibiotic occurrence in honey samples is forbidden.

Fluorinated polymers constitute a unique class of materials that exhibit a combination of suitable properties for a wide range of applications, which mainly arise from their outstanding chemical resistance, thermal stability, low friction coefficients and electrical properties. Furthermore, those presenting stimuli-responsive properties have found widespread industrial and commercial applications, based on their ability to change in a controlled fashion one or more of their physicochemical properties, in response to single or multiple external stimuli such as light, temperature, electrical and magnetic fields, pH and/or biological signals. In particular, some fluorinated polymers have been intensively investigated and applied due to their piezoelectric, pyroelectric and ferroelectric properties in biomedical applications including controlled drug delivery systems, tissue engineering, microfluidic and artificial muscle actuators, among others. This review summarizes the main characteristics, microstructures and biomedical applications of electroactive fluorinated polymers. ; The authors thank the FCT—Fundação para a Ciência e Tecnologia—For financial support under framework of the Strategic Funding UID/FIS/04650/2013, project PTDC/EEI-SII/5582/2014 and project UID/EEA/04436/2013 by FEDER funds through the COMPETE 2020—Programa Operacional Competitividade e Internacionalização(POCI)withthereferenceprojectPOCI-01-0145-FEDER-006941. Funds provided by FCT in the framework of EuroNanoMed 2016 call, Project LungChek ENMed/0049/2016 are also gratefully acknowledged. VFC, DMC, CR and MMF also thank the FCT for the grants SFRH/BPD/98109/2013, SFRH/BPD/121526/2016, SFRH/BPD/90870/2012 and SFRH/BPD/121464/2016, respectively. Finally, the authors acknowledge funding by the Spanish Ministry of Economy and Competitiveness (MINECO) through the project MAT2016-76039-C4-3-R (AEI/FEDER, UE) and from the Basque Government Industry Department under the ELKARTEK program. ...

This work reports the development of renewable cellulose nanocrystal (CNC) and ionic liquid (IL) hybrid materials for bending actuator applications. For this purpose, cellulose nanocrystals with different surface charges (neutral, positive and negative) were prepared and increasing amounts of the IL 2-hydroxy-ethyl-trimethylammonium dihydrogen phosphate ([Ch][DHP]) (10 and 25 wt%) were incorporated into the CNC hosting matrix. The morphology of the samples was evaluated, proving that both surface charge and IL incorporation do not affect the characteristic layered structure of the CNC. Atomic force microscopy results reveal a sea-island morphology in the hybrid films, where CNC bundles are surrounded by [Ch][DHP]-rich regions. An increase in the electrical conductivity is observed upon IL incorporation into the CNC matrix, regardless of the CNC surface charge. The highest electrical conductivity values are observed for IL/CNC (+) 25 wt% with an electrical conductivity of 3.18 x 10(-5) +/- 2.75 x 10(-7) S cm(-1) and IL/CNC (-) 10 wt% (1.26 x 10(-5) +/- 5.92 x 10(-6) S cm(-1)). The highest bending displacement of 2.1 mm for an applied voltage of 4.0 Vpp at a frequency of 100 mHz was obtained for the IL/CNC (+) 25 wt% composite, demonstrating the suitability of cellulose to develop soft actuators. ; The authors thank FCT - Fundacao para a Ciencia e Tecnologia - for financial support under the framework of the Strategic Funding UID/FIS/04650/2019 and UID/QUI/50006/2019 and projects PTDC/BTM-MAT/28237/2017, PTDC/EMD-EMD/28159/2017 and PTDC/FIS-MAC/28157/2017. D. M. C., C. M. C. and L. C. F. also acknowledge FCT for the grants SFRH/BPD/121526/2016, SFRH/BPD/112547/2015 and SFRH/BD/145345/2019, respectively. The authors acknowledge funding by the Spanish State Research Agency (AEI) and the European Regional Development Fund (ERFD) through the project PID2019-106099RB-C43/AEI/10.13039/501100011033 and from the Basque Government Industry and Education Department under the ELKARTEK and PIBA (PIBA-2018-06) programs, ...

Polymer-based piezoelectric biomaterials have already proven their relevance for tissue engineering applications. Furthermore, the morphology of the scaffolds plays also an important role in cell proliferation and differentiation. The present work reports on poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV), a biocompatible, biodegradable, and piezoelectric biopolymer that has been processed in different morphologies, including films, fibers, microspheres, and 3D scaffolds. The corresponding magnetically active PHBV-based composites were also produced. The effect of the morphology on physico-chemical, thermal, magnetic, and mechanical properties of pristine and composite samples was evaluated, as well as their cytotoxicity. It was observed that the morphology does not strongly affect the properties of the pristine samples but the introduction of cobalt ferrites induces changes in the degree of crystallinity that could affect the applicability of prepared biomaterials. Young's modulus is dependent of the morphology and also increases with the addition of cobalt ferrites. Both pristine and PHBV/cobalt ferrite composite samples are not cytotoxic, indicating their suitability for tissue engineering applications. ; The authors thank the FCT (Fundação para a Ciência e Tecnologia) for financial support under the framework of strategic funding UID/FIS/04650/2013, UID/QUI/00686/2013, and UID/QUI/0686/2016; project PTDC/EEI-SII/5582/2014;andprojectPOCI-01-0145-FEDER-028237. FundsprovidedbyFCTintheframeworkof EuroNanoMed2016call,ProjectLungChekENMed/0049/2016arealsogratefullyacknowledged. D.M.C.andC.R. alsothanktheFCTforthegrantsSFRH/BPD/121526/2016andSFRH/BPD/90870/2012,respectively. Finally,the authors acknowledge funding by the Spanish Ministry of Economy and Competitiveness (MINECO) through the project MAT2016-76039-C4-3-R (AEI/FEDER, UE) and from the Basque Government Industry Department under the ELKARTEK and HAZITEK program. ...