TY  - JOUR
A1  - Hrynevich, Andrei
A1  - Achenbach, Pascal
A1  - Jungst, Tomasz
A1  - Brook, Gary A.
A1  - Dalton, Paul D.
T1  - Design of Suspended Melt Electrowritten Fiber Arrays for Schwann Cell Migration and Neurite Outgrowth
JF  - Macromolecular Bioscience
N2  - In this study, well-defined, 3D arrays of air-suspended melt electrowritten fibers are made from medical grade poly(ɛ-caprolactone) (PCL). Low processing temperatures, lower voltages, lower ambient temperature, increased collector distance, and high collector speeds all aid to direct-write suspended fibers that can span gaps of several millimeters between support structures. Such processing parameters are quantitatively determined using a “wedge-design” melt electrowritten test frame to identify the conditions that increase the suspension probability of long-distance fibers. All the measured parameters impact the probability that a fiber is suspended over multimillimeter distances. The height of the suspended fibers can be controlled by a concurrently fabricated fiber wall and the 3D suspended PCL fiber arrays investigated with early post-natal mouse dorsal root ganglion explants. The resulting Schwann cell and neurite outgrowth extends substantial distances by 21 d, following the orientation of the suspended fibers and the supporting walls, often generating circular whorls of high density Schwann cells between the suspended fibers. This research provides a design perspective and the fundamental parametric basis for suspending individual melt electrowritten fibers into a form that facilitates cell culture.
KW  - cell migration
KW  - electrospinning
KW  - fibers
KW  - neurite growth
KW  - polycaprolactone
KW  - tissue engineering
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-257535
VL  - 21
IS  - 7
ER  - 
TY  - JOUR
A1  - Weigel, Tobias
A1  - Brennecke, Julian
A1  - Hansmann, Jan
T1  - Improvement of the electronic—neuronal interface by natural deposition of ECM
JF  - Materials
N2  - The foreign body reaction to neuronal electrode implants limits potential applications as well as the therapeutic period. Developments in the basic electrode design might improve the tissue compatibility and thereby reduce the foreign body reaction. In this work, the approach of embedding 3D carbon nanofiber electrodes in extracellular matrix (ECM) synthesized by human fibroblasts for a compatible connection to neuronal cells was investigated. Porous electrode material was manufactured by solution coelectrospinning of polyacrylonitrile and polyamide as a fibrous porogen. Moreover, NaCl represented an additional particulate porogen. To achieve the required conductivity for an electrical interface, meshes were carbonized. Through the application of two different porogens, the electrodes' flexibility and porosity was improved. Human dermal fibroblasts were cultured on the electrode surface for ECM generation and removed afterwards. Scanning electron microscopy imaging revealed a nano fibrous ECM network covering the carbon fibers. The collagen amount of the ECM coating was quantified by hydroxyproline-assays. The modification with the natural protein coating on the electrode functionality resulted in a minor increase of the electrical capacity, which slightly improved the already outstanding electrical interface properties. Increased cell numbers of SH-SY5Y cell line on ECM-modified electrodes demonstrated an improved cell adhesion. During cell differentiation, the natural ECM enhanced the formation of neurites regarding length and branching. The conducted experiments indicated the prevention of direct cell-electrode contacts by the modification, which might help to shield temporary the electrode from immunological cells to reduce the foreign body reaction and improve the electrodes' tissue integration.
KW  - neuronal electrodes
KW  - carbon fiber
KW  - electrospinning
KW  - ECM coating
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-234047
SN  - 1996-1944
VL  - 14
IS  - 6
ER  -