THERMOGRAVIMETRIC STUDY OF SORBENT BASED ON COVALENTLY IMMOBILIZED ZINC DITHIOCARBAMATE ON A POLYESTER MATRIX.

AbstractMost of the aerial organs of vascular plants are covered by a protective layer known as the cuticle, the main purpose of which is to limit transpirational water loss. Cuticles consist of an amphiphilic polyester matrix, polar polysaccharides that extend from the underlying epidermal cell wall and become less prominent towards the exterior, and hydrophobic waxes that dominate the surface. Here we report that the polarity gradient caused by this architecture renders the transport of water through astomatous olive and ivy leaf cuticles directional and that the permeation is regulated by the hydration level of the cutin-rich outer cuticular layer. We further report artificial nanocomposite membranes that are inspired by the cuticles’ compositionally graded architecture and consist of hydrophilic cellulose nanocrystals and a hydrophobic polymer. The structure and composition of these cuticle-inspired membranes can easily be varied and this enables a systematic investigation of the water transport mechanism.

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Electrical percolation in extrinsically conducting, poly(ε-decalactone) composite neural interface materials

Scientific Reports ◽

10.1038/s41598-020-80361-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Katarzyna Krukiewicz ◽

James Britton ◽

Daria Więcławska ◽

Małgorzata Skorupa ◽

Jorge Fernandez ◽

...

Keyword(s):

Silver Nanowires ◽

Electrochemical Characteristics ◽

Electrical Percolation ◽

Electrically Conducting ◽

Biomedical Device ◽

Conducting Materials ◽

Bidirectional Communication ◽

Polyester Matrix ◽

Electrical Percolation Threshold

AbstractBy providing a bidirectional communication channel between neural tissues and a biomedical device, it is envisaged that neural interfaces will be fundamental in the future diagnosis and treatment of neurological disorders. Due to the mechanical mismatch between neural tissue and metallic neural electrodes, soft electrically conducting materials are of great benefit in promoting chronic device functionality. In this study, carbon nanotubes (CNT), silver nanowires (AgNW) and poly(hydroxymethyl 3,4-ethylenedioxythiophene) microspheres (MSP) were employed as conducting fillers within a poly(ε-decalactone) (EDL) matrix, to form a soft and electrically conducting composite. The effect of a filler type on the electrical percolation threshold, and composite biocompatibility was investigated in vitro. EDL-based composites exhibited favourable electrochemical characteristics: EDL/CNT—the lowest film resistance (1.2 ± 0.3 kΩ), EDL/AgNW—the highest charge storage capacity (10.7 ± 0.3 mC cm− 2), and EDL/MSP—the highest interphase capacitance (1478.4 ± 92.4 µF cm−2). All investigated composite surfaces were found to be biocompatible, and to reduce the presence of reactive astrocytes relative to control electrodes. The results of this work clearly demonstrated the ability of high aspect ratio structures to form an extended percolation network within a polyester matrix, resulting in the formulation of composites with advantageous mechanical, electrochemical and biocompatibility properties.

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