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The regeneration of nerves of the peripheral nervous system after injuries is a complex process. This study presents a novel in vitro neurite regeneration concept to investigate the regeneration of neurons and their processes with different concentrations of neurotrophic factors. The core part of the concept is a transparent microfluidic neurite isolation (NI) device affixed on top of a microelectrode array (MEA), providing a fast and easy way to assess both the growth and the electrical activity of neurites. The NI-MEA isolates neurites from the culture with microchannels that serve as guidance tubes, equipped with microelectrodes. Thus, the NI-MEA allows neurite growth, as observed by microscopy, to be correlated with neurite electrical activity, as measured by electrophysiological recordings. To demonstrate proof of concept of neurite regeneration, we cultured cells from the superior cervical ganglion of postnatal mice under different concentrations of nerve growth factor (NGF). During the regeneration process, we observed an increase in the number of neurites entering the microchannels along with an increase in spike activity recorded by the microelectrodes in the microchannels. We also observed a concentration-dependent effect of neurotrophic factor on the excitability of the growing neurites, with neurites bathed in 20 ng/ml NGF exhibiting enhanced early growth. Thus, our neurite regeneration concept with the NI-MEA device allows further study of neurotrophic factors and reduces the requirement for in vivo experiments on the regeneration of peripheral nerves after injury. © 2015 Wiley Periodicals, Inc.

Magnetic materials synthesized on the nanometer‐scale level are essential for several applications, such as spintronics and magnetologic. As a successful nanofabrication approach, focused electron beam‐induced deposition (FEBID) stands out as a direct‐write technique. FEBID uses an electron beam to locally induce a CVD process, avoiding the use of masks and resists. In this work, Fe–based nanostructures are synthesized on Si(100) by FEBID, starting from iron pentacarbonyl. A systematic variation of FEBID parameters is performed, to study their influence on the geometry and composition of the deposit. Based on the results, specific deposition conditions are suggested for magneto‐logic applications and fabrication of large structures.

Among various multi‐metal combinations, Au‐Fe nanoalloys are envisaged as prospective materials for data storage applications. Here we report on the first successful achievement of Au‐Fe nanoalloys using focused electron beam‐induced deposition (FEBID), exploiting the possibility of directly writing nanostructures at nanometer resolution. Gaseous organometallic precursors are injected simultaneously into the deposition chamber to co‐deposit Fe and Au within the same nanostructure. Fabricated nanostructures show a spatially uniform elemental ratio of iron to gold that can be tailored by experimental conditions.

Focused electron beam induced deposition (FEBID) is a novel direct-writing technique to produce noble metal nanostructures. In this work, FEBID has been employed for the first time to fabricate metal-oxide-semiconductor capacitors (MOSCAPs). Experimental parameters such as precursor temperature, substrate temperature and the (de)focus of the electron beam have been optimized to deposit electrode structures of a relatively large area within a short timeframe. Using FEBID, gold electrodes have been deposited on top of an atomic layer deposited (ALD) dielectric aluminum oxide layer. Chemical composition of the produced structures has been studied using energy dispersive X-ray spectroscopy (EDX). Current–voltage (I–V) measurements have confirmed the conductivity of FEBID gold nanowires (NWs). Measured capacitance–voltage (C–V) characteristics of FEBID-fabricated MOSCAP prototypes resemble the typical C–V characteristics of conventionally fabricated MOSCAPs, thus confirming the functionality of our FEBID devices. Illustration of a MOS capacitor fabricated by FEBID.

The capability to control matter down to the nanoscale level in combination with the novel magnetic properties of nanomaterials have attracted increasing attention in the last few decades due to their applications in magnetic sensing, hard disc data storage and logic devices. Therefore, many efforts have been devoted to the implementation of both nanofabrication methods as well as characterization of magnetic nanoelements. In this study, Fe-based nanostructures have been synthesized on Si(100) by focused electron beam induced deposition (FEBID) utilizing iron pentacarbonyl as precursor. The so obtained nanostructures exhibit a remarkably high iron content (Fe > 80 at.%), expected to give rise to a ferromagnetic behaviour. For that reason, magnetic force microscopy (MFM) analyses were performed on the obtained FEBID Fe nanostructures. Moreover, object oriented micromagnetic framework (OOMMF) magnetic simulations have been executed to study the influence of the geometry on the magnetic properties of iron single-domain nanowires. FEBID is a mask-less nanofabrication method based on the injection of precursor gas molecules in proximity of the deposition area where their decomposition is locally induced by a focused electron beam.