Stable and productive biofilms are highly attractive for continuous whole-cell biocatalysis, yet their controlled formation and long-term operation remain challenging. Here, we introduce a modular and scalable microfluidic reactor platform that exploits flow-induced deposition to generate robust biofilms directly from suspended cells. Starting from a validated pillar reactor design, we systematically scale reactor geometries and apply computational flow simulations to identify microscale hydrodynamic features that govern cell attachment, streamer formation, and biofilm stability. Fluorescence microscopy reveals the emergence of stratified biofilm architectures enriched in extracellular DNA that persist under continuous flow. Enzymatic depletion of extracellular DNA selectively delays early streamer formation, highlighting its critical role during initial matrix assembly. Under continuous flow, biofilm growth and shear-induced detachment establish a dynamic steady state that maintains a self-sustaining catalytic matrix, enabling long-term continuous whole-cell biocatalysis in an upscaled reactor where the deposited biofilms remain catalytically active and structurally stable for at least 28 days. Together, these results establish flow-structured microreactors as a generalizable strategy for hydrodynamically controlled biofilm engineering, linking microscale flow fields to biofilm architecture, long-term stability, and catalytic function, and providing a foundation for scalable continuous whole-cell biocatalysis.

As a high-resolution, cost-effective, and rapid fabrication method, near-field electrospinning enables the formation of micro- and nanostructures, positioning it as a promising tool also for advanced nanomanufacturing. However, stable fabrication of sub-100-nm well-aligned fibers remains challenging due to the complex interplay of process parameters. In this work, reliable nanofiber fabrication is established using a custom-built near-field electrospinning setup, based on a micro-printhead having an inner nozzle diameter below 50 & micro;m. A voltage-based classification of jetting region cutoff, fiber formation, and supersaturation is proposed, indicating that continuous nanofiber fabrication is only achievable within a fiber formation parameter region. Thus, augmented by an increase in the relative printhead-substrate velocity, well-placed nanofibers with diameters down to 50 nm are fabricated reproducibly. Additionally, the influence of nozzle outlet size on the required operating voltage and resulting fiber morphology is investigated. This work deepens understanding of the near-field electrospinning process and provides a robust and precise method for fabricating polymer nanofibers as low as 25 nm diameter, contributing a decided advance in facile 3D nanostructuring.

An autoclavable microfluidic bioreactor (MBR) with an integrated gas-liquid contactor based on an ultra-thin permeable and transparent membrane enables a systematic analysis of intra-plant communication. The bioreactor units can be cascaded in a downstream manner, driven by a perfusion stream, to provide one-directional paths for allelochemical communication. Our article details a manufacturing pathway that achieves wrinkle-free membranes in these autoclaveable chips, by applying a drumhead-stretching design to the installed membrane. Traditional ultrasonic welding was used in the end as the bonding process, but absorber-free laser transmission welding was tested as well, and the results are reported in this article. In addition, we evaluated the membrane-stretching-behavior theoretically through simulations. The results of this analysis were then applied to the membrane installation. Through the new design and the application of the membrane stretching analysis, a reduction of the wrinkle amplitude in the installed membrane of on average over 80

Tissue engineering scaffolds are pivotal for modern healthcare research. However, studying cell-cell and cell-material interactions within these scaffolding networks is time consuming and technically demanding. In most cases, the cells within the scaffolds are not visible to classical imaging technologies, so what happens within remains unknown. An emerging non-destructive option for studying cells within scaffolds is micro-magnetic resonance imaging (mu-MRI). In this research, its applications to imaging cells within tissue engineering scaffolds during different periods and quantifying colonization processes within pyrolytic carbon networks for their special physical-chemical properties are explored and discussed. Additionally, toward resource-efficient tissue engineering, in silico approaches are raising the attention of the research community. These simulations can be performed employing cellular automata interacting with computer-aided design (CAD) models, which mimic cell colonization of scaffolds. Our study demonstrates that mu-MRI proves a remarkable technology for fine-tuning these computational models.

ABSTRACTLaser‐induced forward transfer (LIFT) printing uniquely enables localized deposition of nanoparticle pastes onto target substrates. The extent of its versatility hinges upon the availability of nanoparticle inks that align with the capabilities of the printing device. Given the inherent distinctions among various devices attributed to differences in laser types (continuous‐wave or pulsed), laser energy profiles, and adaptable wavelengths, ink formulation and the LIFT printing processes are frequently disjointed, which results in a lengthy optimization cycle. Significantly expedited optimization cycles could be achieved if LIFT performance of an ink could be tested on‐site of the ink developer. This localization empowers ink developers to tailor inks precisely to specific usage scenarios by promptly adjusting parameters such as particle size, viscosity, and surface properties. This paper presents a dedicated LIFT device that focuses on fine‐tuning ink characteristics and provides insights into the construction to allow other interested researchers to build similar low‐cost, user‐friendly setups.

Temperature is a key driver of microbial metabolism, yet non-invasive methods for quantifying microbially generated heat in complex environments remain limited. Here, we present a low-cost digital temperature sensing system integrated into an Arduino-controlled data acquisition setup to monitor microbial activity in stratified Winogradsky columns, which are self-contained sediment microcosms that reproduce natural oxygen and sulfide gradients. Localized temperature differences of up to 0.55 ± 0.04 °C were detected between aerobic and anaerobic layers, consistent with microbial heat generation in active sediment zones. Short-term insulation experiments further amplified these effects, demonstrating that microbial thermogenesis can serve as a reliable proxy for metabolic activity. Compared with infrared thermography or isothermal microcalorimetry, the proposed approach is simple, cost-effective, and compatible with aqueous and stratified systems. The method enables real-time, non-invasive observation of microbial metabolic dynamics and establishes a framework for continuous thermal monitoring in living environmental microcosms.

Abstract. Additive manufacturing has enabled rapid prototyping of components with minimum investment in specific fabrication infrastructure. These tools allow a fast iteration from design to functional prototypes within days or even hours. Such prototyping technologies exist in many fields, from 3-dimensional mechanical components, or printed electric circuit boards (PCBs) for electrical connectivity, to mention two. In the case of nuclear magnetic resonance (NMR) spectroscopy one needs the combination of both fields, we need to fabricate three-dimensional electrically conductive tracks as coils that are wrapped around a sample container. Fabricating such structures is difficult (e.g. 6 axes micro-milling) or simply not possible with conventional methods. In this paper, we modified an additive manufacturing method that is based on the extrusion of conductive ink to fastprototype solenoidal coil designs for NMR. These NMR coils, need to be as close to the sample as possible and by their shape have specific inductive values. The performance of the designs was first investigated using EM-field simulations, and circuit simulations. The coil found to have optimal parameters for NMR was fabricated by extrusion printing and its performance was tested in a 1.05 T imaging magnet. The objective is to demonstrate reproducible rapid prototyping of complicated designs with high precision that as a side effect hardly produces material waste during production.

A custom-built laser-induced forward transfer (LIFT) setup was developed to fabricate multimaterial organic light emitting diode (OLED) stacks under ambient laboratory conditions without the use of a cleanroom or encapsulation. The process enables precise control of layer thickness through parameter tuning as confirmed by vertical scanning interferometry (VSI), yielding smooth and homogeneous layers with surface roughness values down to . The process achieves tunable thicknesses between 19 nm and 45 nm, while the lateral resolution is limited to about . A three-layer OLED stack (total thickness ) was printed and structurally characterized using focused ion beam scanning electron microscopy (FIB-SEM) and time-of-flight secondary ion mass spectrometry (ToF-SIMS), revealing distinct, well-defined layer boundaries. First functional tests demonstrated electroluminescence at with an operational lifetime of at least . Despite the lack of encapsulation, the OLEDs remained stable under ambient conditions with a shelf life of up to days. These results confirm the potential of LIFT as a scalable and precise tool for the additive manufacturing of flexible thin-film devices such as OLEDs, solar cells and fuel cells.

Additive manufacturing has enabled rapid prototyping of components with minimum investment in specific fabrication infrastructure. These tools allow for a fast iteration from design to functional prototypes within days or even hours. Such prototyping technologies exist in many fields, including three-dimensional mechanical components and printed electric circuit boards (PCBs) for electrical connectivity, to mention two. In the case of nuclear magnetic resonance (NMR) spectroscopy, one needs the combination of both fields; we need to fabricate three-dimensional electrically conductive tracks as coils that are wrapped around a sample container. Fabricating such structures is difficult (e.g., six-axis micro-milling) or simply not possible with conventional methods. In this paper, we modified an additive manufacturing method that is based on the extrusion of conductive ink to fast-prototype solenoidal coil designs for NMR. These NMR coils need to be as close to the sample as possible and, by their shape, have specific inductive values. The performance of the designs was first investigated using electromagnetic field simulations and circuit simulations. The coil found to have optimal parameters for NMR was fabricated by extrusion printing, and its performance was tested in a 1.05 T imaging magnet. The objective is to demonstrate reproducible rapid prototyping of complicated designs with high precision that, as a side effect, hardly produces material waste during production.

This work introduces a general solution for printing wavelength-selective bulk-heterojunction photosensitive organic field effect transistors (PS-OFETs) by addressing electrode thickness variation and the feasibility of color selectivity in detecting incident light. The inkjet-printed silver electrode thickness was varied from 125 to 950 nm by multilayer printing. PIF, IDFBR, and ITIC-4F were chosen as the active semiconductor materials with complementary optical absorption. Results indicate that PS-OFETs exhibit the best functionality at an electrode thickness of approximately 325 nm and an active material combination with PIF:IDFBR (1:1). For the 540 nm wavelength, a responsivity of 55 mAW−1 was obtained. This is four-fold higher than the photoresponse obtained at 700 nm.

Capacitors play a crucial role in modern electronics as they are widely employed for energy storage, signal processing, radiofrequency tuning and matching, and signal filtering. This paper presents a novel approach to chip-scale capacitor fabrication utilizing the laser-induced forward transfer (LIFT) technique, a versatile 3D printing method that offers a flexible and cost-effective alternative to conventional manufacturing processes. Plate capacitors were fabricated through dot-by-dot printing of titanium di-oxide and silver paste layers, and their performance evaluated. Optimal dot circularity at a diameter of 130 mu ${\rm{\mu }}$m were achieved with printing parameters of 120 mW for 4 ms, with no noticeable surface defects. Using smaller dots enabled higher resolution, but this compromised the quality of the printed surface. The fabricated capacitors demonstrated a mean capacity of 40.1 +/- $\pm $ 2.2 pF at 100 MHz, making them suitable also for high-frequency applications. The resistivity of the printed silver tracks was 1.2 x 1 0- 7 Omega m $1.2\,\times \,1{0}<^>{-7}\,{\rm{\Omega }}{\rm{m}}$, measured over 16 structures, and closely matched the manufacturer's specifications for the silver ink. The achieved resolution from the dot-by-dot method used in this paper provided greater flexibility in transfer in comparison to previously reported results using a square-shaped transfer geometry.

In recent decades, electrokinetic handling of microparticles and biological cells found many applications ranging from biomedical diagnostics to microscale assembly. The integration of electrokinetic handling such as dielectrophoresis (DEP) greatly benefits microfluidic point-of-care systems as many modern assays require cell handling. Compared to traditional pump-driven microfluidics, typically used for DEP applications, centrifugal CD microfluidics provides the ability to consolidate various liquid handling tasks in self-contained discs under the control of a single motor. Therefore, it has significant advantages in terms of cost and reliability. However, to integrate DEP on a spinning disc, a major obstacle is transferring power to the electrodes that generate DEP forces. Existing solutions for power transfer lack portability and availability or introduce excessive complexity for DEP settings. We present a concept that leverages the compatibility of DEP and inductive power transfer to bring DEP onto a rotating disc without much circuitry. Our solution leverages the ongoing advances in the printed circuit board market to make low-cost cartridges (<$1) that can employ DEP, which was validated using yeast cells. The resulting DEPDisc platform solves the challenge that existing printed circuit board electrodes are reliant on expensive high-voltage function generators by boosting the voltage using resonant inductive power transfer. This work includes a device costing less than $100 and easily replicable with the information provided in the Supplementary material. Consequently, with DEPDisc we present the first DEP-based low-cost platform for cell handling where both the device and the cartridges are truly inexpensive.

Artificial microtextures adopted to achieve adhesion reduction help avoid the vulnerability associated with chemical coatings. Most current microtextures strongly rely on biological inspiration or designers' physical intuition. There are also manufacturing challenges due to the complex geometrical configurations. Topology optimization can determine the structural configurations encompassing geometric information on topology, shape, and size and ensure the manufacturability of the optimized microtextures by controlling the feature size corresponding to a specified fabrication process. Herein, we present an approach to reduce the liquid adhesion on solid surfaces by employing artificial microtextures with hexagonal periodicity, where the microtextures are inversely designed through topology optimization. The microtextures are fabricated of polydimethylsiloxane by using a soft lithography process. The liquid adhesion on the microtextures is measured via the tilting plate method. Experimental results demonstrate that the topologically optimized microtextures can significantly reduce the liquid adhesion by 45.0%, which is achieved by the robust Cassie-Baxter state of the wetting behavior. The topologically optimized microtextures can also support the robust Cassie-Baxter state underwater and accelerate the speed when the droplets slide off the surface with them. The findings can be utilized in the context of the reduction of underwater drag and bioadhesion.

Laser-induced graphene (LIG) has been emerging as a promising electrode material for supercapacitors due to its cost-effective and straightforward fabrication approach. However, LIG-based supercapacitors still face challenges with limited capacitance and stability. To overcome these limitations, in this work, we present a novel, cost-effective, and facile fabrication approach by integrating LIG materials with candle-soot nanoparticles. The composite electrode is fabricated by laser irradiation on a Kapton sheet to generate LIG material, followed by spray-coating with candle-soot nanoparticles and annealing. Materials characterization reveals that the annealing process enables a robust connection between the nanoparticles and the LIG materials and enhances nanoparticle graphitization. The prepared supercapacitor yields a maximum specific capacitance of 15.1 mF/cm(2) at 0.1 mA/cm(2), with a maximum energy density of 2.1 mu Wh/cm(2) and a power density of 50 mu W/cm(2). Notably, the synergistic activity of candle soot and LIG surpasses the performances of previously reported LIG-based supercapacitors. Furthermore, the cyclic stability of the device demonstrates excellent capacitance retention of 80% and Coulombic efficiency of 100% over 10000 cycles.

Additive micro/nano-manufacturing of polymeric precursors combining with a subsequent pyrolysis step enables the design-controlled fabrication of micro/nano-architected 3D pyrolytic carbon structures with complex architectural details. Pyrolysis results in a significant geometrical shrinkage of the pyrolytic carbon structure, leading to a structural dimension significantly smaller than the resolution limit of the involved additive manufacturing technology. Combining with the material properties of carbon and 3D architectures, architected 3D pyrolytic carbon exhibits exceptional properties, which are significantly superior to that of bulk carbon materials. This article presents a comprehensive review of the manufacturing processes of micro/nano-architected pyrolytic carbon materials, their properties, and corresponding demonstrated applications. Acknowledging the "young" age of the field of micro/nano-architected carbon, this article also addresses the current challenges and paints the future research directions of this field.

BACKGROUND:Biomedical diagnostic and lab automation solutions built on the Lab-on-a-Disc (LoaD) platform has great potential due to their independence from specialised micro-pumps and their ease of integration, through direct pipetting, with manual or automated workflows. However, a challenge for all microfluidic chips is their cost of manufacture when each microfluidic disc must be customized for a specific application. In this paper, we present centrifugal discs with programmable fluidic networks.RESULTS:Based on dissolvable film valves, we present two technologies. The first, based on recently introduced pulse-actuated dissolvable film valves, is a centrifugal disc which, depending on how it is loaded, is configured to perform either six sequential reagent releases through one reaction chamber or three sequential reagent releases through two reaction chambers. In the second approach, we use the previously introduced electronic Lab-on-a-Disc (eLoaD) wireless valve array, which can actuate up to 128 centrifugo-pneumatic dissolvable film valves in a pre-defined sequence. In this approach we present a disc which can deliver any one of 8 reagent washes to any one of four reaction chambers. We use identical discs to demonstrate the first four sequential washes through two reaction chambers and then two sequential washes through four reaction chambers.SIGNIFICANCE:These programmable fluidic networks have the potential to allow a single disc architecture to be applied to multiple different assay types and so can offer a lower-cost and more integrated alternative to the standard combination of micro-titre plate and liquid handling robot. Indeed, it may even be possible to conduct multiple different assays concurrently. This can have the effect of reducing manufacturing costs and streamlining supply-chains and so results in a more accessible diagnostic platform.

The integration of additive manufacturing technologies with the pyrolysis of polymeric precursors enables the design-controlled fabrication of architected 3D pyrolytic carbon (PyC) structures with complex architectural details. Despite great promise, their use in cellular interaction remains unexplored. This study pioneers the utilization of microarchitected 3D PyC structures as biocompatible scaffolds for the colonization of muscle cells in a 3D environment. PyC scaffolds are fabricated using micro-stereolithography, followed by pyrolysis. Furthermore, an innovative design strategy using revolute joints is employed to obtain novel, compliant structures of architected PyC. The pyrolysis process results in a pyrolysis temperature- and design-geometry-dependent shrinkage of up to 73%, enabling the geometrical features of microarchitected compatible with skeletal muscle cells. The stiffness of architected PyC varies with the pyrolysis temperature, with the highest value of 29.57 ± 0.78 GPa for 900 °C. The PyC scaffolds exhibit excellent biocompatibility and yield 3D cell colonization while culturing skeletal muscle C2C12 cells. They further induce good actin fiber alignment along the compliant PyC construction. However, no conclusive myogenic differentiation is observed here. Nevertheless, these results are highly promising for architected PyC scaffolds as multifunctional tissue implants and encourage more investigations in employing compliant architected PyC structures for high-performance tissue engineering applications.

We report on a portable dielectrophoresis manipulation platform, for the positioning and immobilization of small dielectric objects, such as cells or microbes, using a circular array of up to six symmetrically arranged and independently controllable micro-electrodes. The system’s micro-controller-instructed electronic drivers can be operated in three distinct modes. We demonstrate the system’s function by actuating bacterial cells to specific locations and orientations within a region of interest. Using a deep learning approach, we map voltage phase combinations of the six electrodes to geometrical trap position locations, thereby facilitating smooth trajectory planning.

This paper reports on ADEPT (short for Adaptable DEP Embedded Platform Tool) – a unique dielectrophoresis (DEP) setup comprising a six-electrodes DEP microfluidic chip and its control electronics. The latter is an ultra-versatile control unit with the following characteristics: (i) built with off-the-shelf components, (ii) enables independent control in amplitude, frequency and phase of the voltage signals applied to multiple electrodes, (iii) universal and scalable – can be used in combination with different application-specific micro-electrode designs and can be extended to larger number of control signals, (iv) intuitive user interface. While DEP has been used extensively in a large number of applications [1], the present implementation is unique due to the following capabilities: (i) positioning precision of 3μm of a single particle (beads or cells) which is unprecedented for a non-CMOS implementation [2]; (ii) first demonstration of reversible separation/mixing in a non-flow DEP configuration; (iii) combined trapping and electrorotation at the precise desired trapping position.

This work presents the fabrication of candle-soot (CS) nanofibers through electrospinning and demonstrates their use as high-performance electrodes for supercapacitors. The electrospinning is facilitated by dispersing CS nanoparticles within a precursor polymer solution, which is carbonized to obtain free-standing CS/carbon nanofiber electrodes. The electrodes exhibit superior electrochemical performance when compared to pristine carbon nanofibers. The fabricated supercapacitor yields a maximum capacitance of 433.5 F/g at 0.5 mA/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> current density, with a maximum energy density of 60.2 Wh/kg, at a power density of 283.1 W/kg, which is also significantly superior compared to reported carbon nanofiber-based supercapacitors.