Application Areas

Magnetic remote actuation of soft materials is attractive for applications such as transforming materials and medical robots. However, due to manufacturing limitations, microscale magnetoactive devices are scarce and light-based additive manufacturing methods, despite achieving microscale resolution, struggle with particle-induced light scattering. Moreover, large hard-magnetic microparticles restrict ultimate feature sizes and deformation of soft-magnetic nanoparticle composites requires impractically high loading and field gradients. Among successfully fabricated microscale soft-magnetic composites, limited control over particle loading, distribution, and matrix-phase stiffness has hindered their functionality. Here, we combine two-photon polymerization with iron oxide nanoparticle co-precipitation to fabricate 3D-printed microscale nanocomposites with spatially tunable nanoparticle distribution. We controlled nanoparticle content by locally modulating the two-photon dose, imbuing parts with varied magnetic functionality and achieving millimeter-scale elastic deformations, demonstrated by a soft robotic gripper and a bistable bit register and sensor. Our approach enables precise control of mechanical and magnetic properties toward microscale metamaterial and robotics applications.

Endovascular interventions—i.e., minimally invasive procedures that involve navigating guidewires and/or microcatheters through a patient’s vasculature to access target treatment sites—have emerged as a preferable alternative to traditional open surgery in many clinical contexts. Unfortunately, maneuverability constraints inherent to conventional guidewire-microcatheter systems can hinder effective navigation to target sites, elevating the risk of procedural complications or failed catheterization. Soft robotic surgical instruments that harness fluidic actuation schemes hold unique promise to overcome such challenges; however, manufacturing-induced limitations remain a critical barrier to their miniaturization, reproducibility, and clinical translation. To address these issues, in this work, a novel additive manufacturing strategy is presented to realize fluidically steerable soft robotic microcatheters via “two-photon direct laser writing (DLW)”. As an exemplar relevant to 3-French (1 mm-in-diameter) microcatheters used for transarterial chemoembolization (TACE), a 3D-printed soft microrobotic tip is fabricated, which enables localized steering driven by microfluidic inputs while simultaneously facilitating fluidic payload delivery through a central lumen. By providing a pathway to new classes of soft robotic microsurgical instruments that enable on-demand steerability via fluidic means, the presented strategy offers notable potential for navigating narrow, complex, tortuous, and/or delicate vasculature to enhance the safety and efficacy of endovascular therapy.

We present a scalable cryo-CMOS controller for color-center-based quantum processors. A diamond waveguide micro-chiplet with NVs is pick-and-placed on CMOS with a 3D-printed prism for scalable photonic readout. A serial qubit driver array using grid inductors and pulse-width modulators generates a programmable 2.87GHz magnetic field for each qubit with low power and strong confinement. Up to 144 qubits can be operated on a single chip, with 204μW power consumption per qubit under active control.

Magnetic remote actuation of soft materials is attractive for applications such as transforming materials and medical robots. However, due to manufacturing limitations, microscale magnetoactive devices are scarce and light-based additive manufacturing methods, despite achieving microscale resolution, struggle with particle-induced light scattering. Moreover, large hard-magnetic microparticles restrict ultimate feature sizes and deformation of soft-magnetic nanoparticle composites requires impractically high loading and field gradients. Among successfully fabricated microscale soft-magnetic composites, limited control over particle loading, distribution, and matrix-phase stiffness has hindered their functionality. Here, we combine two-photon polymerization with iron oxide nanoparticle co-precipitation to fabricate 3D-printed microscale nanocomposites with spatially tunable nanoparticle distribution. We controlled nanoparticle content by locally modulating the two-photon dose, imbuing parts with varied magnetic functionality and achieving millimeter-scale elastic deformations, demonstrated by a soft robotic gripper and a bistable bit register and sensor. Our approach enables precise control of mechanical and magnetic properties toward microscale metamaterial and robotics applications.

Magnetic remote actuation of soft materials is attractive for applications such as transforming materials and medical robots. However, due to manufacturing limitations, microscale magnetoactive devices are scarce and light-based additive manufacturing methods, despite achieving microscale resolution, struggle with particle-induced light scattering. Moreover, large hard-magnetic microparticles restrict ultimate feature sizes and deformation of soft-magnetic nanoparticle composites requires impractically high loading and field gradients. Among successfully fabricated microscale soft-magnetic composites, limited control over particle loading, distribution, and matrix-phase stiffness has hindered their functionality. Here, we combine two-photon polymerization with iron oxide nanoparticle co-precipitation to fabricate 3D-printed microscale nanocomposites with spatially tunable nanoparticle distribution. We controlled nanoparticle content by locally modulating the two-photon dose, imbuing parts with varied magnetic functionality and achieving millimeter-scale elastic deformations, demonstrated by a soft robotic gripper and a bistable bit register and sensor. Our approach enables precise control of mechanical and magnetic properties toward microscale metamaterial and robotics applications.

Surface modifications of polycaprolactone (PCL) implants influence osseointegration by altering cell adhesion, proliferation, and differentiation. Osteon-like microtopography has been shown to enhance these parameters compared to untreated PCL. Additional treatments, such as cold atmospheric plasma (CAP) and extracellular matrix (ECM) coatings, may further improve bioactivity. This study evaluates and compares the osteogenic potential of osteon-like microtopography, CAP treatment on non-microstructured PCL, ECM coating on non-microstructured PCL, and their combination. Modified PCL samples were analyzed for cell adhesion, proliferation, and differentiation using primary human mesenchymal stem cells. Compared to osteon-like microtopography, CAP-treated and ECM-coated surfaces the combination of all three increased cell adhesion by nearly two-fold. Cell proliferation followed a similar trend, with the combination treatment showing the greatest enhancement by day 10. Alkaline phosphatase activity peaked with osteon-like microtopography, while mineralization was maximized with the combination treatment. In summary, the integration of osteon-like microtopography with CAP treatment and ECM coating synergistically improves cell adhesion, proliferation, and differentiation, offering a promising strategy for optimizing PCL implants to improve osseointegration.

Magnetic remote actuation of soft materials is attractive for applications such as transforming materials and medical robots. However, due to manufacturing limitations, microscale magnetoactive devices are scarce and light-based additive manufacturing methods, despite achieving microscale resolution, struggle with particle-induced light scattering. Moreover, large hard-magnetic microparticles restrict ultimate feature sizes and deformation of soft-magnetic nanoparticle composites requires impractically high loading and field gradients. Among successfully fabricated microscale soft-magnetic composites, limited control over particle loading, distribution, and matrix-phase stiffness has hindered their functionality. Here, we combine two-photon polymerization with iron oxide nanoparticle co-precipitation to fabricate 3D-printed microscale nanocomposites with spatially tunable nanoparticle distribution. We controlled nanoparticle content by locally modulating the two-photon dose, imbuing parts with varied magnetic functionality and achieving millimeter-scale elastic deformations, demonstrated by a soft robotic gripper and a bistable bit register and sensor. Our approach enables precise control of mechanical and magnetic properties toward microscale metamaterial and robotics applications.

In this work, we demonstrate the fabrication as well as immediate application of 3D printed spiral phase plates on the ends of FC/PC fiber adapter ferrule tips using a NanoOne 1000 two-photon polymerization 3D printer from UpNano. The spiral phase plates were fabricated to alter the orbital angular momentum of incoming light, and a direct application of modal filtering in an indoor, short-range, free-space optical communication link was shown. The mode conversion quality of six different 3D printed spiral phase plates on ferrule tips is presented. An l=4 and an l=−4 spiral phase plate were chosen to demonstrate the ability to suppress an aggressing Gaussian signal in a free-space communication link, with the l=4 being printed on a FC/PC ferrule tip used as the transmit, and the l=−4 printed on a glass slide in the receive architecture of the system. Multiple iterations of the experiment were performed, and it was found that the 3D printed structures were able to suppress the aggressing Gaussian beam on average by approximately 32.7 dB and allowed for error-free communication at 10 Gbps on a vortex beam with the co-propagating aggressor at an identical wavelength to the communication link.

Endovascular interventions—i.e., minimally invasive procedures that involve navigating guidewires and/or microcatheters through a patient’s vasculature to access target treatment sites—have emerged as a preferable alternative to traditional open surgery in many clinical contexts. Unfortunately, maneuverability constraints inherent to conventional guidewire-microcatheter systems can hinder effective navigation to target sites, elevating the risk of procedural complications or failed catheterization. Soft robotic surgical instruments that harness fluidic actuation schemes hold unique promise to overcome such challenges; however, manufacturing-induced limitations remain a critical barrier to their miniaturization, reproducibility, and clinical translation. To address these issues, in this work, a novel additive manufacturing strategy is presented to realize fluidically steerable soft robotic microcatheters via “two-photon direct laser writing (DLW)”. As an exemplar relevant to 3-French (1 mm-in-diameter) microcatheters used for transarterial chemoembolization (TACE), a 3D-printed soft microrobotic tip is fabricated, which enables localized steering driven by microfluidic inputs while simultaneously facilitating fluidic payload delivery through a central lumen. By providing a pathway to new classes of soft robotic microsurgical instruments that enable on-demand steerability via fluidic means, the presented strategy offers notable potential for navigating narrow, complex, tortuous, and/or delicate vasculature to enhance the safety and efficacy of endovascular therapy.

Flow past obstacle clusters in micro-channels is central to a wide range of microfluidic applications, yet its fundamental hydrodynamics remain poorly understood under strong geometric confinement.

No-slip boundary conditions on all walls enforce inherently three-dimensional (3D) flow structures in fully confined micro-channels, fundamentally altering wake formation, momentum transport, and drag mechanisms. A combined experimental and numerical investigation of wake dynamics behind obstacle clusters in laminar micro-channel flows is presented. High-resolution micro-particle image velocimetry and resolved 3D computational fluid dynamics simulations are employed to systematically explore the effects of Reynolds number and cluster porosity. We demonstrate that full wall confinement suppresses classical wake–regime transitions commonly observed in shallow and unconfined flows, including shear layer instabilities and vortex shedding. Instead, wake recovery is governed primarily by secondary flows that promote rapid momentum redistribution across the channel depth. As a result, wake length exhibits only weak dependence on Reynolds number and is controlled predominantly by cluster porosity. We further introduce the relative bleeding velocity as a unifying metric to characterize the transition from macro-particle to individual particle behavior. The relative bleeding velocity is the ratio of the mean velocity through the cluster’s main axis perpendicular to the inflow and the mean inflow velocity. These findings establish a distinct physical regime of confined wake flows, bridging the gap between classical shallow flow theory and microfluidic hydrodynamics, and provide a foundation for improved prediction of pressure losses, transport, and mixing in micro-reactors and porous microfluidic systems.

Efficient mixing in microfluidic systems is bottlenecked by laminar flow and diffusion-dominated transport, limiting the performance of biochemical assays such as conversion rates of enzymatic processes. Here, we present an acoustofluidic micromixer based on two-photon polymerization (2PP)-printed three-dimensional microneedles that act as ultrasonic microresonators to generate localized acoustic streaming. The freeform arrangement of the microneedles enables integration into diverse microfluidic channel layouts and produces strong, tunable streaming vortices that enhance transport. We characterize the streaming flow fields as a function of actuation frequency, and demonstrate rapid and voltage-dependent mixing with a 2.5-fold enhancement. When applied to the alkaline phosphatase–fluorescein diphosphate (ALP–FDP) reaction, acoustic mixing doubles the fluorescein signal under optimal conditions and significantly reduces the assay time and channel footprint required in continuous flow. These resultsdemonstrate that 3D microneedle-based acoustofluidics is a compact, versatile, and integrable solution for enhancing transport-limited biochemical processes in lab-on-a-chip systems.

Diseases or injuries that affect neuromuscular tissues severely impact human health, motivating the development of in vitro models of the motor control system. Current platforms either have limited reproducibility or require complex fabrication protocols that preclude high-resolution imaging and scalable functional analysis. We have developed a one-step method for fabricating an all-hydrogel limb-on-a-chip that addresses key challenges of current systems by enabling reproducible and scalable manufacturing of neuromuscular tissues compartmentalized into “spinal cord” and “limb” chambers. Co-cultures of motor neurons and skeletal muscles within this platform enable longitudinal tracking of neuromuscular junction formation and visualization of changes in muscle contraction in response to motor neuron stimulation. We demonstrate tissue-wide recordings of muscle force and single-cell-resolution measurements of muscle calcium activity. Our accessible method for fabricating reproducible in vitro neuromuscular models that are compatible with high-resolution imaging and functional readouts provides a powerful tool for investigating the neuromuscular interface in health and disease.

Efficient mixing in microfluidic systems is bottlenecked by laminar flow and diffusion-dominated transport, limiting the performance of biochemical assays such as conversion rates of enzymatic processes. Here, we present an acoustofluidic micromixer based on two-photon polymerization (2PP)-printed three-dimensional microneedles that act as ultrasonic microresonators to generate localized acoustic streaming. The freeform arrangement of the microneedles enables integration into diverse microfluidic channel layouts and produces strong, tunable streaming vortices that enhance transport. We characterize the streaming flow fields as a function of actuation frequency, and demonstrate rapid and voltage-dependent mixing with a 2.5-fold enhancement. When applied to the alkaline phosphatase–fluorescein diphosphate (ALP–FDP) reaction, acoustic mixing doubles the fluorescein signal under optimal conditions and significantly reduces the assay time and channel footprint required in continuous flow. These resultsdemonstrate that 3D microneedle-based acoustofluidics is a compact, versatile, and integrable solution for enhancing transport-limited biochemical processes in lab-on-a-chip systems.

Purpose
Surface micropatterning is being explored as a strategy to mitigate thrombus formation and reduce long-term anticoagulation requirements in left ventricular assist devices (LVADs). This study investigated whether specific micro-topographies can modulate platelet deposition under LVAD supraphysiological wall shear stress (WSS) conditions.

Materials and Methods
A custom microfluidic platform was developed to generate a linear WSS gradient from 16 to 130 Pa. Microchannels were patterned with reverse cones and hemispheres in small (1–3 µm) and large (3–9 µm) sizes using two-photon polymerization and nanoimprinting. Human blood was perfused through the microchannels, and platelet deposition was quantified over time as the area coverage ratio (Aₚₗₜ/Aₜₒₜ) and area under the curve (AUC). Platelet detachment events were counted as an indicator of thrombus stability, and computational simulations supported the interpretation of local shear conditions.

Results
Consistent trends emerged, although no statistical differences were observed relative to flat controls. Aₚₗₜ/Aₜₒₜ increased with WSS for all surfaces. At 16 Pa, small and large cones reduced platelet adhesion by approximately 84 and 98%, respectively, compared to flat controls. At 49 Pa, the reduction was about 95% for small cones and 80% for large cones. Conical geometries also promoted platelet washout at higher WSS. Small hemispherical features showed more than 50% lower platelet adhesion than flat surfaces for WSS > 16 Pa, with limited thrombus growth.

Conclusion
Conical micropatterns may be most effective at limiting platelet adhesion at lower WSS, while small hemispheres may perform better at higher WSS. These trends suggest a surface–shear interaction that warrants further investigation for LVAD surface optimization.

Chromosome-less minicells, derived from aberrant polar division events of bacterial cells, have emerged as promising nanocarriers for targeted cancer drug delivery due to their unique characteristics. A major challenge in their purification process lies in effectively isolating such spherical minicells (< 1 μm) from their rod-shaped parental cells (1–10 μm). This study investigates the use of Deterministic Lateral Displacement (DLD) microfluidic systems for minicell purification, leveraging Two-Photon Lithography (TPL) for the rapid prototyping of high-resolution designs optimized for this purpose. Under laminar flow conditions, we investigated key DLD design parameters including symmetric and asymmetric post gaps, outlet widths, dual post arrays, fluidic-resistance-optimized design. To enhance separation efficiency, we developed a two-stage microfluidic separation system combining a spiral inertial chip and an optimized DLD chip in series. Utilizing high-resolution TPL for chip fabrication of an inertial chip with 12 spirals and an asymmetric DLD chip with a 2 μm downstream post gap, we achieved a separation efficiency of 94%. This high efficiency achieved using microfluidics for the separation of cells differing in both shape and size, demonstrates the potential of advanced microfluidic systems in cell sorting.

Electrochemical sensors offer the advantages of low cost, high sensitivity, and miniaturization for a wide range of biological applications, including in situ detection of cell metabolites and monitoring cell behavior in real time. However, the complex matrix in biosystems often leads to electrode fouling and inferior sensing performance. In addition to chemical barriers featuring assorted antifouling molecules or coatings, creating micro/nano hierarchical structures on top of electrodes can provide physical barriers to mitigate matrix interference without affecting electron transfer. The emerging two-photon polymerization (TPP) 3D printing technique with the capability to produce precise submicron to several micrometer features on a variety of substrates has enabled the straightforward fabrication of complex hierarchical structures. In this paper, we integrate the value-added micro/nanostructures made by TPP printing with the interdigitated electrode-based sensors and demonstrate the platform’s advantages in filtering out small interfering micro-objects and thus reducing matrix effects. Applying the novel approach to real-time cell monitoring, a 3D-printed microstructure-integrated platform shows higher sensitivity (i.e., the slope of the calibration curve) to model redox analytes in cell culture medium compared to bare electrodes, which display compromised sensitivity due to cell passivation. This research opens a new avenue for mitigating matrix interference and enhancing electrochemical sensing with significant implications across a broad range of applications.