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Magnetic resonance tomography typically applies the Fourier transform to k-space signals repeatedly acquired from a frequency encoded spatial region of interest, therefore requiring a stationary object during scanning. Any movement of the object results in phase errors in the recorded signal, leading to deformed images, phantoms, and artifacts, since the encoded information does not originate from the intended region of the object. However, if the type and magnitude of movement is known instantaneously, the scanner or the reconstruction algorithm could be adjusted to compensate for the movement, directly allowing high quality imaging with non-stationary objects. This would be an enormous boon to studies that tie cell metabolomics to spontaneous organism behaviour, eliminating the stress otherwise necessitated by restraining measures such as anesthesia or clamping. In the present theoretical study, we use a phantom of the animal model C. elegans to examine the feasibility to automatically predict its movement and position, and to evaluate the impact of movement prediction, within a sufficiently long time horizon, on image reconstruction. For this purpose, we use automated image processing to annotate body parts in freely moving C. elegans, and predict their path of movement. We further introduce an MRI simulation platform based on bright field videos of the moving worm, combined with a stack of high resolution transmission electron microscope (TEM) slice images as virtual high resolution phantoms. A phantom provides an indication of the spatial distribution of signal-generating nuclei on a particular imaging slice. We show that adjustment of the scanning to the predicted movements strongly reduces distortions in the resulting image, opening the door for implementation in a high-resolution NMR scanner., PLoS Computational Biology, 15 (12), ISSN:1553-734X, ISSN:1553-7358

Continuous development of fabrication technologies, such as two-photon polymerization (2PP), allows the exact reconstruction of specific volume shapes at micro- and nanometer precision. Advancements in the engineering of new materials, such as ionic liquids (ILs), are bringing superior advantages in terms of material characteristics, facilitating a combination of optical and electrical properties, as well as lithographic capabilities. In this paper, 2PP is utilized for structuring of a novel IL–polymer composite in a single-step manufacturing process with high resolution, down to 200 nm, and high aspect ratio, up to 1:20. The composition, based on a photosensitive photoresist (e.g., IP-L 780 or SU-8) and the IL 1-butyl-3-methylimidazolium dicyanamide, possesses a good ionic conductivity (in the range of 1–10 mS cm−1) over a wide frequency bandwidth (1 kHz–1 MHz), an electrochemical window of 2.7 V, and a good optical transparency (transmission value of 90% for a 170 μm thick film). The fabricated structures are characterized and the phenomenon of enhanced conductivity (up to 4 S cm−1) is explained. Two potential applications, including temperature and relative humidity sensing, are demonstrated as examples. The results suggest a new advanced approach for material structuring that can be regarded as highly most promising for a wide range of applications.

The in vivo analysis of a small multicellular organism such as the nematode Caenorhabditis elegans, enables fundamental biomedical and environmental studies of a complete organism under normal physiological conditions. Continuous advancements in photonics, electronics, as well as the material sciences, are paving the way towards miniaturized bioanalytical systems, known as labs-on-a-chip (LOC). These microfluidic technologies facilitate the manipulation and study of nematodes in a precise, real-time, portable, and cost-effective manner, potentially for high throughput operation. In this paper we review all currently available “worm-on-a-chip” miniaturized systems that address the manipulation, detection, and study of the sensory response of C. elegans, and take a close look at their advantages, application challenges, and scientific potential. The paper aims to consolidate recent results of dedicated worm microsystems that target a better understanding of C. elegans.

A key challenge in micro- and nanotechnology is the direct patterning of functional structures. For example, it is highly desirable to possess the ability to create three-dimensional (3D), conductive, and optically transparent structures. Efforts in this direction have, to date, yielded less than optimal results since the polymer composites had low optical transparency over the visible range, were only slightly conductive, or incompatible with high resolution structuring. We have previously presented the novel cross-linkable, conductive, highly transparent composite material based on a photoresist (IP-L 780, OrmoComp, or SU-8) and the ionic liquid 1-butyl-3-methylimidazolium dicyanamide. Material patterning by conventional and two-photon photolithography has been demonstrated as proof-of-concept. Aiming to increase the resolution and to extend the spectrum of exciting applications we continued our research into identifying new ionic liquid - polymer composites. In this paper, we report the precise 3D single-step structuring of optically transparent and electrically conductive ionic liquid - polymer nanostructures with the highest spatial resolution (down to 150 nm) achieved to date. This was achieved via the development of novel cross-linkable composite based on the photoresist IP-G 780 and the ionic liquid 1-butyl-3-methylimidazolium dicyanamide. The successful combination of the developed material with the advanced direct laser writing technique enabled the time- and cost-saving direct manufacturing of transparent, electrically conductive components. We believe that the excellent characteristics of the structured material will open a wider range of exciting applications.

a b s t r a c t We demonstrate that chip-integrated BubbleJet technology can be used for cell sorting as well as for single-cell lysis. Vapor bubbles on the millisecond timescale are generated by titanium microheaters manufactured on transparent glass wafers. A PDMS layer is bonded on top of the glass wafer and defines microfluidic channels. Cell sorting is demonstrated with mouse fibroblasts which are hydrodynamically focused and travel at velocities of about 500 m/s. For cell sorting the bubble generators are placed outside the microfluidic channel but are connected to it via a 20 m nozzle. Randomly selected fibroblasts have been deflected laterally up to 60 m from their original streamline to a collector outlet by actuation. Single-cell lysis is performed by bubble generators placed inside a flow channel directly below the cells' path. Bubble generation pushes the cells towards the channel ceiling or the channel wall and cells are lysed due to the large shear force at an efficiency of 100%. Cycle times for sorting and lysis have experimentally been determined to be 5 ms and 20 ms, respectively.

The in vivo analysis of a model organism, such as the nematode Caenorhabditis elegans, en‐ ables fundamental biomedical studies, including development, genetics, and neurobiolo‐ gy. In recent years, microfluidics technology has emerged as an attractive and enabling tool for the study of the multicellular organism. Advances in the application of microflui‐ dics to C. elegans assays facilitate the manipulation of nematodes in high-throughput for‐ mat and allow for the precise spatial and temporal control of their environment. In this chapter, we aim to illustrate the current microfluidic approaches for the investigation of behavior and neurobiology in C. elegans and discuss the trends of future development.

A novel crosslinkable, conductive, highly transparent composite material based on a photoresist and an ionic liquid (the names of the composites are not announced here due to the current procedure of patenting) is presented. The composite possesses a good and stable ionic conductivity (up to 10 mS cm−1 at room temperature) over a wide frequency bandwidth (1 kHz – 1 MHz) and is optically transparent (transmission value of 90 % for a 170 µm thick film). In addition, an approach for the patterning of the composite material by conventional photolithography with a good spatial resolution (line width of 20 – 30 µm) is introduced. The unique properties of the material are utilized for time- and cost-saving direct manufacturing of electrically conductive, highly transparent microcomponents.