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Fast, nondestructive three-dimensional (3D) imaging of live suspension cells remains challenging without substrate treatment or fixation, precluding scalable single-cell morphometry with minimal alterations. While optical sectioning techniques achieve 3D live cell imaging, lateral versus depth resolution differences further complicate analysis. We present a scalable microfluidic method capable of 3D fluorescent isotropic imaging of live, nonadherent cells suspended inside picoliter droplets with high-speed single-cell volumetric readout (800 to 1,200 slices in 5 to 8 s) and near-diffraction limit resolution (~216 nm). The platform features a droplet trap array that leverages flow-induced droplet interfacial shear to generate intradroplet microvortices, which rotate single cells on their axis to enable optical projection tomography (OPT)-based imaging. This allows gentle (~1 mPa shear stress) observation of cells encapsulated inside nontoxic isotonic buffer droplets, facilitating scalable OPT acquisition by simultaneous spinning of hundreds of cells. We demonstrate 3D imaging of live myeloid and lymphoid cells in suspension, including K562 cells, as well as naive and activated T cells-small cells prone to movement in their suspended phenotype. Our fully suspended, orientation-independent cell morphometry, driven by isotropic imaging and spherical harmonic analysis, enabled the study of primary T cells across various immunological activation states. This approach unveiled six distinct nuclear content distributions, contrasting with conventional 2D images that typically portray spheroid and bean-like nuclear shapes associated with lymphocytes. Our arrayed-droplet OPT technology is capable of isotropic, single live-cell 3D imaging, with the potential to perform large-scale morphometry of immune cell effector function states while providing compatibility with microfluidic droplet operations.

Enhanced mixing in microfluidic systems is necessary in many applications such as chemical processing, biological assays, and diagnosis. We are developing a microfluidic system to efficiently mix minute reagents (down to several microliters) using vibration-induced flow (VIF), in which a net flow is generated around a micropillar by applying periodic vibration. In this study, we numerically investigate the enhancement in chaotic mixing using the VIF technique and periodic switching of vibrations. By extending our previous numerical simulation model, we investigate the flow field and trajectories of fluid particles in three-dimensional space. We demonstrate that chaotic advection characteristics can be observed by periodically switching the vibrational direction of a substrate using simple cylindrical pillars. In addition, using an appropriate interval for switching the vibration axes yields better mixing performance. The extent of chaotic advection is evaluated quantitatively using the Lyapunov exponent considering various vibration parameters, such as the vibration amplitude, separation distance between each pillar and pillar shape. The flow field induced by a large-amplitude and sharp-edged wall pillar provides excellent mixing results. Thus, VIF is successfully applied to obtain an efficient mixing strategy with the aid of the chaotic theory. [ABSTRACT FROM AUTHOR]

Archived patient-derived tissue specimens play a central role in understanding disease and developing therapies. To address specificity and sensitivity shortcomings of existing single-cell resolution proteoform analysis tools, we introduce a hybrid microfluidic platform (DropBlot) designed for proteoform analyses in chemically fixed single cells. DropBlot serially integrates droplet-based encapsulation and lysis of single fixed cells, with on-chip microwell-based antigen retrieval, with single-cell western blotting of target antigens. A water-in-oil droplet formulation withstands the harsh chemical (SDS, 6 M urea) and thermal conditions (98 °C, 1-2 hr) required for effective antigen retrieval, and supports analysis of retrieved protein targets by single-cell electrophoresis. We demonstrate protein-target retrieval from unfixed, paraformaldehyde-fixed (PFA), and methanol-fixed cells. Key protein targets (HER2, GAPDH, EpCAM, Vimentin) retrieved from PFA-fixed cells were resolved and immunoreactive. Relevant to biorepositories, DropBlot profiled targets retrieved from human-derived breast tumor specimens archived for six years, offering a workflow for single-cell protein-biomarker analysis of sparing biospecimens.

Period phase gradient metasurface plays a great role in promoting the innovation of acoustic application devices. However, harnessing the internal thermal viscosity of the period phase gradient metasurface to realize sound absorption and non-reciprocal transmission faces the narrow working frequency band and uncontrollable efficiency. In this paper, we propose a lossy metasurface by embedded microperforated walls to realize sound redirection and absorption with high efficiency than 90% simultaneously. The phase modulation is realized using an opening channel, which can cover the 2 π phase range in a broadband frequency range by changing the channel depth. The loss introduced by the microperforated walls can achieve efficient sound energy dissipation when negative reflection occurs. The functions can be switched between wave redirection and wave absorption by rotating the metasurface. In addition, this metasurface can redirect the incident wave below −10° and absorb the incident wave above 25° over a wide frequency range from 1500 to 6500 Hz. The simulation and experiment results of our design are in excellent agreement. This research provided a new bridge to integrate wave redirection and absorption with microperforated walls and may have potential applications in acoustic sensing, sound source identification, and mechanical fault diagnosis. [ABSTRACT FROM AUTHOR]

Despite much progress, image processing remains a significant bottleneck for high-throughput analysis of microscopy data. One popular platform for single-cell time-lapse imaging is the mother machine, which enables long-term tracking of microbial cells under precisely controlled growth conditions. While several mother machine image analysis pipelines have been developed in the past several years, adoption by a non-expert audience remains a challenge. To fill this gap, we implemented our own software, MM3, as a plugin for the multidimensional image viewer napari. napari-MM3 is a complete and modular image analysis pipeline for mother machine data, which takes advantage of the high-level interactivity of napari. Here, we give an overview of napari-MM3 and test it against several well-designed and widely used image analysis pipelines, including BACMMAN and DeLTA. Researchers often analyze mother machine data with custom scripts using varied image analysis methods, but a quantitative comparison of the output of different pipelines has been lacking. To this end, we show that key single-cell physiological parameter correlations and distributions are robust to the choice of analysis method. However, we also find that small changes in thresholding parameters can systematically alter parameters extracted from single-cell imaging experiments. Moreover, we explicitly show that in deep learning-based segmentation, what you put is what you get (WYPIWYG) - that is, pixel-level variation in training data for cell segmentation can propagate to the model output and bias spatial and temporal measurements. Finally, while the primary purpose of this work is to introduce the image analysis software that we have developed over the last decade in our lab, we also provide information for those who want to implement mother machine-based high-throughput imaging and analysis methods in their research.

BackgroundVagal afferent neurons represent the key neurosensory branch of the gut-brain axis, which describes the bidirectional communication between the gastrointestinal system and the brain. These neurons are important for detecting and relaying sensory information from the periphery to the central nervous system to modulate feeding behavior, metabolism, and inflammation. Confounding variables complicate the process of isolating the role of the vagal afferents in mediating these physiological processes. Therefore, we developed a microfluidic model of the sensory branch of the gut-brain axis. We show that this microfluidic model successfully compartmentalizes the cell body and neurite terminals of the neurons, thereby simulates the anatomical layout of these neurons to more accurately study physiologically-relevant processes.MethodsWe implemented a primary rat vagal afferent neuron culture into a microfluidic platform consisting of two concentric chambers interconnected with radial microchannels. The microfluidic platform separated cell bodies from neurite terminals of vagal afferent neurons. We then introduced physiologically-relevant gastrointestinal effector molecules at the nerve terminals and assessed their retrograde transport along the neurite or capacity to elicit an electrophysiological response using live cell calcium imaging.ResultsThe angle of microchannel outlets dictated the probability of neurites growing into a chamber versus tracking along chamber walls. When the neurite terminals were exposed to fluorescently-labeled cholera toxin subunit B, the proteins were taken up and retrogradely transported along the neurites over the course of 24 h. Additionally, mechanical perturbation (e.g., rinsing) of the neurite terminals significantly increased intracellular calcium concentration in the distal soma. Finally, membrane-displayed receptor for capsaicin was expressed and trafficked along newly projected neurites, as revealed by confocal microscopy.ConclusionsIn this work, we developed a microfluidic device that can recapitulate the anatomical layout of vagal afferent neurons in vitro. We demonstrated two physiologically-relevant applications of the platforms: retrograde transport and electrophysiological response. We expect this tool to enable controlled studies on the role of vagal afferent neurons in the gut-brain axis.

Crystals of trans-3,3′-dimethylazobenzene (DMAB) exhibit crawling motion on solid surface upon simultaneous exposure to ultraviolet (UV) and visible light from opposite directions. In this study, the shape and velocity during the photoinduced crawling motion of DMAB crystals are successfully controlled by irradiation light intensities. A higher intensity of the visible light than the UV light causes the crystals to be spread shape and move slower (∼1 μm min−1). In contrast, a stronger UV light allows them to be droplet-like shape and move faster (∼4 μm min−1). The shape and velocity can be varied by adjusting the light intensities. Shape transformation is effectively applied to cargo capture–carry–release tasks. In particular, spread-shaped crystals capture silica particles over a wide area, whereas droplet-like crystals gather and transport them. This result suggests that a multifunctional soft transporter composed of a single component does not require complex fabrication, thereby contributing to the fields of soft robotics and microfluidics. [ABSTRACT FROM AUTHOR]

Surfactant plays a crucial role in the chemical enhanced oil recovery (cEOR) process, and in‐situ emulsification is regarded as one of the mechanisms for surfactant flooding. However, no direct evidences are available so far to show how emulsions are generated in porous media, and how emulsification is essential for cEOR. To address these issues, binary mixtures of several currently‐used sulfonate surfactants, SH5, SH6, and SHZ, were formulated with connate brine to displace crude oil in both 2D microfluidic chips and 3D glass beads porous media, as well as artificial cores. It was found that both “oil‐in‐water” (O/W) and “water‐in‐oil” (W/O) macroemulsions can be formed in‐situ inside the porous media, and they improve oil recovery mainly through breaking residual oil into small drops and improving mobility ratio, which can significantly reduce the residual oil saturation by up to 12.8% in 2D microchips. The in‐situ emulsification in 3D glass beads medium can get oil recovery factor up to 15% over water flooding. In‐situ formulation of microemulsion was also observed in microfluidic flow tests. Part of the oil phase is emulsified into microemulsions that are present in the middle phase, further mobilizing the oil trapped downstream, lowering residual oil saturation from 54.8% to 11.3% in 2D microchips, and enhancing oil recovery factor up to 25% in core flooding test. These findings advance insightful understanding of in‐situ emulsification during surfactant flooding process under simulated oil reservoir condition, offering real‐time evidence of how both macro‐ and micro‐emulsions formation help for cEOR. [ABSTRACT FROM AUTHOR]

Detecting glucose levels is crucial for diabetes patients as it enables timely and effective management, preventing complications and promoting overall health. In this endeavor, we have designed a novel, affordable point-of-care diagnostic device utilizing microfluidic principles, a smartphone camera, and established laboratory colorimetric methods for accurate glucose estimation. Our proposed microfluidic device comprises layers of adhesive poly-vinyl films stacked on a poly methyl methacrylate (PMMA) base sheet, with micro-channel contours precision-cut using a cutting printer. Employing the gold standard glucose-oxidase/peroxidase reaction on this microfluidic platform, we achieve enzymatic glucose determination. The resulting colored complex, formed by phenol and 4-aminoantipyrine in the presence of hydrogen peroxide generated during glucose oxidation, is captured at various glucose concentrations using a smartphone camera. Raw images are processed and utilized as input data for a 2-D convolutional neural network (CNN) deep learning classifier, demonstrating an impressive 95% overall accuracy against new images. The glucose predictions done by CNN are compared with ISO 15197:2013/2015 gold standard norms. Furthermore, the classifier exhibits outstanding precision, recall, and F1 score of 94%, 93%, and 93%, respectively, as validated through our study, showcasing its exceptional predictive capability. Next, a user-friendly smartphone application named "GLUCOLENS AI" was developed to capture images, perform image processing, and communicate with cloud server containing the CNN classifier. The developed CNN model can be successfully used as a pre-trained model for future glucose concentration predictions. [ABSTRACT FROM AUTHOR]

Multiple respiratory viruses lead to high morbidity and mortality, yet global surveillance platforms focus primarily on seasonal influenza viruses. The COVID-19 pandemic and new RSV vaccines highlight the importance of a broader approach. Upper respiratory tract swabs from children aged 24–59 months presenting with influenza-like illness in The Gambia were collected during follow-up of a live-attenuated influenza vaccine randomised controlled trial in 2017–18. A microfluidic quantitative polymerase chain reaction (qPCR) assay was established and used to detect 21 respiratory viruses. 76.6% of samples had one or more viruses detected (n = 121/158). The viruses detected most frequently were rhinovirus (n = 37/158, 23.4%) and adenovirus (n = 34/158, 21.5%), followed by parainfluenza virus 3, influenza B and human metapneumovirus B. A third of positive samples had multiple viruses detected (two n = 31/121, 25.6%; three n = 9/121, 7.4%). Our data demonstrates how microfluidic qPCR is a useful tool for high-throughput, comprehensive detection of multiple respiratory viruses in surveillance platforms. Rapidly changing epidemiology exemplifies the need for new, broader approaches to virus surveillance in low-resource settings to respond to future epidemics and to guide the need for and use of new prevention and therapeutic measures. [ABSTRACT FROM AUTHOR]

The synaptic connections between dorsal root ganglia (DRG) and dorsal horn (DH) neurons are a crucial relay point for the transmission of painful stimuli. To delineate how synaptic plasticity may modulate the excitability of DH neurons, we have devised a microfluidic co-culture model that recapitulates the first sensory synapse using postnatal mouse sensory neurons. We show that DRG-DH co-cultures characterize salient features of the in vivo physiology of sensory neurons. Immunocytcochemical experiments of the cultured DH neurons show a co-localization of Map2 with VGlut2 and of Map2 with Synapsin 1, corroborating the glutamatergic identity of the DH neurons and further suggesting the potential formation of active synapses in this neuronal set. Fluorometric imaging experiments demonstrate the elicitation of calcium responses in DH neurons following the stimulation of DRG cell bodies or axons. Selective NMDA and AMPA receptor blockade appreciably silences DH neuron responses, suggesting that glutamatergic signaling is maintained in vitro. Last, a surrogate model of peripheral nerve injury is introduced in the form of an axotomy, which results in elevated and prolonged calcium responses of DH neurons. Overall, the microfluidic mouse co-cultures provide a method advancement in the study of periphery-to-center pain signaling, where the potential of utilizing the platform for drug target identification is underscored. [ABSTRACT FROM AUTHOR]

[Display omitted] Our hypothesis is that dynamic interfacial tension values as measured by the partitioned-Edge-based Droplet GEneration (EDGE) tensiometry can be connected to those obtained with classical techniques, such as the automated drop tensiometer (ADT), expanding the range of timescales towards very short ones. Oil-water and air–water interfaces are studied, with whey protein isolate solutions (WPI, 2.5 – 10 wt%) as the continuous phase. The dispersed phase consists of pure hexadecane or air. The EDGE tensiometer and ADT are used to measure the interfacial (surface) tension at various timescales. A comparative assessment is carried out to identify differences between protein concentrations as well as between oil–water and air–water interfaces. The EDGE tensiometer can measure at timescales down to a few milliseconds and up to around 10 s, while the ADT provides dynamic interfacial tension values after at least one second from droplet injection and typically is used to also cover hours. The interfacial tension values measured with both techniques exhibit overlap, implying that the techniques provide consistent and complementary information. Unlike the ADT, the EDGE tensiometer distinguishes differences in protein adsorption dynamics at protein concentrations as high as 10 wt% (which is the highest concentration tested) at both oil–water and air–water interfaces. [ABSTRACT FROM AUTHOR]

Engineered liver lobule is highly practical in hepatic disease treatment, while constructing a 3D biomimetic lobule with a heterogeneous architecture on a large scale is challenging. Here, inspired by the natural architectural construction of hepatic lobules, biomimetic hepatic lobules are proposed with coaxially through‐pores for nutrient exchange via microfluidic technology. This multi‐channel microfluidic chip is made by parallelly installing capillaries. Sodium alginate (Alg) is pumped through its central channel, while Ca2+‐loaded gelatin methacrylate (GelMA) solutions encapsulating hepatocytes, mesenchymal stem cells, and endothelia cells are pumped through surrounding channels, respectively. The rapid gelation of Alg and Ca2+ brings about an in situ formation of Alg fiber, with heterogeneous multi‐cell‐laden GelMA microcarriers forming around it. The peeled‐off microcarriers each featured with a coaxially through pore, simulating the cord‐like structure of hepatic lobule and facilitating nutrients exchange. Meanwhile, the spatially anisotropic arrangement of cells highly simulates the hepatic architecture. It is demonstrated that by transplanting these biomimetic microparticles into liver in situ, the failed liver in rat shows increased regeneration and decreased necrosis. These results indicated that the microfluidic multi‐compartmental microcarriers provide a new strategy to engineer 3D artificial livers for clinical translation. [ABSTRACT FROM AUTHOR]

Emerging diagnostic scenarios, such as population surveillance by pooled testing and on‐site rapid diagnosis, highlight the importance of advanced microfluidic systems for in vitro diagnostics. However, the widespread adoption of microfluidic technology faces challenges due to the lack of standardized design paradigms, posing difficulties in managing macro‐micro fluidic interfaces, reagent storage, and complex macrofluidic operations. This paper introduces a novel modular‐based mesoscopic design paradigm, featuring a core "needle‐plug/piston" structure with versatile variants for complex fluidic operations. These structures can be easily coupled with various microfluidic platforms to achieve truly self‐contained microsystems. Incorporated into a "3D extensible" design architecture, the mesoscopic design meets the demands of function integration, macrofluid manipulations, and flexible throughputs for point‐of‐care nucleic acid testing. Using this approach, an ultra‐sensitive nucleic acid detection system is developed with a limit of detection of ten copies of SARS‐CoV‐2 per mL. This system efficiently conducts large‐scale pooled testing from 50 pharyngeal swabs in a tube with an uncompromised sensitivity, enabling a truly "sample‐in‐answer‐out" microsystem with exceptional performance. [ABSTRACT FROM AUTHOR]

Selecting strains with superior traits from strain improvement strategies is challenging, as it involves navigating the fitness landscape by applying selective pressures that drive variants from peaks of improvement to valleys over time. In recent years, the screening and selection is conducted via droplet microfluidic methods due to its high throughput capabilities. However, the oft‐used binary strategy, targeting only the high levels of improved traits, may not reflect the overall enhancement. A multiplexed sorting method capable of applying an additional threshold to sort traits by phenotypic strength is reported. The novel approach uses a droplet‐digital microfluidic sorter to screen different volumes of droplets using the same device design and sorting parameters. This method is used to sort glucoamylase enzyme mutants with two levels of activity (medium and high) from libraries of diastatic yeast that have been mutated with non‐genetically modified techniques. Using the multiplex system, medium‐performing strains with enhanced (up to 60%) fermentation kinetics in synthetic beverage media, which would have been missed with a binary screening approach, are identified. The multiplex sorting strategy efficiently finds strains with superior fermentation traits in the fitness landscape without requiring extensive screening rounds and mutations. [ABSTRACT FROM AUTHOR]

The importance of microfluidics research is growing, especially in the fields of chemistry, biology or medicine. This is coupled with a growing demand for specialized capillary equipment that allows advanced research at the microscale. Conventional methods of manufacturing such devices are expensive, time-consuming and do not guarantee good results. An alternative to these methods is the use of 3D printing technology. Despite the existence of numerous works presenting the possibilities of 3D printing in the context of creating microfluidic devices, there is a lack of comprehensive works presenting qualitative analysis of printed objects. This paper presents a method of producing microcapillary structures for microfluidics research with the help of 3D printing using stereolithography technology. The quality requirements that the printed objects should meet are defined and all stages of production are characterized. A qualitative analysis of the obtained objects was carried out, taking into account both the influence of individual printing parameters and print processing methods. The results of microfluidic tests using printed objects are also presented. This work is aimed at providing specific knowledge that allows the manufacture of precision devices for microfluidics purposes at low cost. [ABSTRACT FROM AUTHOR]

Flow rate is one of the most important parameters used in various applications, including biomedical engineering and industrial applications. PDMS has been considered a biocompatible material for making flow sensors. Measuring low flows is one of the upcoming challenges in using this type of flowmeter. This study aims to examine the potential of PDMS microcantilevers to measure the low flow rates in microfluidic networks for biological applications. For this purpose, this study attempts to increase the sensitivity and accuracy of a PDMS microcantilever-based flow meter. The effect of the microcantilever's shape on the device's sensitivity is investigated. The fluid interaction with the PDMS structure is studied using the finite element method (FEM) to measure the beam's deformation. Results indicate that the best shape for the cantilever in the flow meter to have the highest accuracy and sensitivity is the bio-mimic model inspired by octopus arms. The sensitivity and accuracy of the flow sensor using this model increased by 157% and 53.8% compared to those in previous models, respectively. [ABSTRACT FROM AUTHOR]

The current experimental investigation demonstrates the capability of neutron imaging to quantify cavitation, in terms of vapour content, within an orifice of an abruptly constricting geometry. The morphology of different cavitation regimes setting in was properly visualised owing to the high spatial resolution of 16 μm achieved, given the extensive field of view of 12.9 × 12.9 mm2 offered by the imaging set-up. At a second step, the method was proven capable of highlighting subtle differences between fluids of different rheological properties. More specifically, a reference liquid was comparatively assessed against a counterpart additised with a Quaternary Ammonium Salt (QAS) agent, thus obtaining a viscoelastic behaviour. In accordance with previous studies, it was verified, yet in a quantifiable manner, that the presence of viscoelastic additives affects the overall cavitation topology by promoting the formation of more localised vortical cavities rather than cloud-like structures occupying a larger portion of the orifice core. To the authors' best knowledge, the present work is the first to demonstrate that neutron imaging is suitable for quantifying in-nozzle cavitating flow at the micrometre level, consequently elucidating the distinct forms of vaporous structures that arise. The potential of incorporating neutron irradiation for the quantification of two-phase flows in metallic microfluidics devices has been established. [ABSTRACT FROM AUTHOR]

The demand for glucose monitoring devices has witnessed continuous growth from the rising diabetic population. The traditional approach of blood glucose (BG) sensor strip testing generates only intermittent glucose readings. Interstitial fluid‐based devices measure glucose dynamically, but their sensing approaches remain either minimally invasive or prone to skin irritation. Here, a sweat glucose monitoring system is presented, which completely operates under rest with no sweat stimulation and can generate real‐time BG dynamics. Osmotically driven hydrogels, capillary action with paper microfluidics, and self‐powered enzymatic biochemical sensor are used for simultaneous sweat extraction, transport, and glucose monitoring, respectively. The osmotic forces facilitate greater flux inflow and minimize sweat rate fluctuations compared to natural perspiration‐based sampling. The epidermal platform is tested on fingertip and forearm under varying physiological conditions. Personalized calibration models are developed and validated to obtain real‐time BG information from sweat. The estimated BG concentration showed a good correlation with measured BG concentration, with all values lying in the A+B region of consensus error grid (MARD = 10.56% (fingertip) and 13.17% (forearm)). Overall, the successful execution of such osmotically driven continuous BG monitoring system from passive sweat can be a useful addition to the next‐generation continuous sweat glucose monitors. [ABSTRACT FROM AUTHOR]

Forensic case samples collected in sexual assaults typically contain DNA from multiple sources, which complicates short‐tandem repeat (STR) profiling. These samples are typically sent to a laboratory to separate the DNA from sperm and non‐sperm sources prior to analysis. Here, the automation and miniaturization of these steps using digital microfluidics (DMF) is reported, which may eventually enable processing sexual assault samples outside of the laboratory, at the point of need. When applied to vaginal swab samples collected up to 12 h post‐coitus (PC), the new method identifies single‐source (male) STR profiles. When applied to samples collected 24–72 h PC, the method identifies mixed STR profiles, suggesting room for improvement and/or potential for data deconvolution. In sum, an automated, miniaturized sample pre‐processing method for separating the DNA contained in sexual assault samples is demonstrated. This type of automated processing using DMF, especially when combined with Rapid DNA Analysis, has the potential to be used for processing of sexual assault samples in hospitals, police offices, and other locations outside of the laboratory. [ABSTRACT FROM AUTHOR]

This article reports the synthesis of a novel perfluoropolyalkylether (PFPAE) vinylether monomer and its use as a comonomer in the thiol‐ene photopolymerization of a trifunctional thiol together with a trifunctional vinylether. The crosslinked copolymers are obtained in the form of few mm thick layers and characterized. By changing the thiol/ene ratio, the polymers are optimized to tailor their surface composition and obtain adhesion between two thick layers despite the presence of the fluorinated monomer. The final bilayered structures are adhesive, and appeared chemically resistant, with good dimensional stability: therefore, these fluorinated thiol–ene based copolymers are likely to be of interest for applications based on layer‐by‐layer processes, such as additive manufacturing and microfluidics. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles have attracted great attention and become promising candidates in the biomedicine field due to their special physicochemical properties. They are generally divided into metallic and non‐metallic magnetic nanoparticles, according to their compositions. Both of the two types have shown practical values in biomedicine applications, such as drug delivery, biosensing, bioimaging, and so on. Research efforts are devoted to the improvement of synthesis strategies to achieve magnetic nanoparticles with controllable morphology, diverse composition, active surface, or multiple functions. Taking high repeatability, programmable operation, precise fluid control, and simple device into account, the microfluidics system can expand the production scale and develop magnetic nanoparticles with desired features. This review will first describe different classifications of promising magnetic nanoparticles, followed by the advancements in microfluidic synthesis and the latest biomedical applications of these magnetic nanoparticles. In addition, the challenges and prospects of magnetic nanoparticles in the biomedical field are also discussed. [ABSTRACT FROM AUTHOR]

Artificial intelligence (AI) is revolutionizing medicine by automating tasks like image segmentation and pattern recognition. These AI approaches support seamless integration with existing platforms, enhancing diagnostics, treatment, and patient care. While recent advancements have demonstrated AI superiority in advancing microfluidics for point of care (POC) diagnostics, a gap remains in comparative evaluations of AI algorithms in testing microfluidics. We conducted a comparative evaluation of AI models specifically for the two-class classification problem of identifying the presence or absence of bubbles in microfluidic channels under various imaging conditions. Using a model microfluidic system with a single channel loaded with 3D transparent objects (bubbles), we challenged each of the tested machine learning (ML) (n = 6) and deep learning (DL) (n = 9) models across different background settings. Evaluation revealed that the random forest ML model achieved 95.52% sensitivity, 82.57% specificity, and 97% AUC, outperforming other ML algorithms. Among DL models suitable for mobile integration, DenseNet169 demonstrated superior performance, achieving 92.63% sensitivity, 92.22% specificity, and 92% AUC. Remarkably, DenseNet169 integration into a mobile POC system demonstrated exceptional accuracy (>0.84) in testing microfluidics at under challenging imaging settings. Our study confirms the transformative potential of AI in healthcare, emphasizing its capacity to revolutionize precision medicine through accurate and accessible diagnostics. The integration of AI into healthcare systems holds promise for enhancing patient outcomes and streamlining healthcare delivery. [ABSTRACT FROM AUTHOR]

Nowadays, the methods of manufacturing microfluidic mixers were not flexible enough to customize and manufacture special sizes. Hence, a novel electrohydrodynamic jet printing method was proposed to fabricate cross‐scale mold for manufacturing micromixers in one step. Polyvinylpyrrolidone (PVP)/polycaprolactone (PCL) composite ink was prepared, and various printing parameters were investigated for fabricating varieties of 2D structures and 3D regular molds. A cross‐scale spiral mixer was successfully printed, various diameter ratio of 5.6, aspect ratio of 7.2. The PVP/PCL lines were direct printed, size of 66 nm deep and 743 nm wide. The circles were size of 564 nm deep and 7.02 μm wide. The mixing conditions of micromixers with different width ratios were simulated and analyzed; and the better mixing effect of micromixers with width ratio of 2:1 was proved, improved the mixing efficiency by 15.6% compared with micromixer without cross‐scale channels. The cross‐scale micromixers are promising for skin chip sensor and drug metabolite analysis, and the printing method proposed in this paper has great application potential in micro‐electro‐mechanical systems (MEMS). [ABSTRACT FROM AUTHOR]

The study's goals are to fabricate PLGA nanoparticles (PNPs) loaded with apigenin (AP) and adenosine (AD) using a microfluidic preparation method to a standard emulsification method and investigate the possible heart-protective effects of AP-AD PNPs made using the emulsification method. Compared to microfluidics, the emulsification method fabricated small-size nanoparticles, which are better at encapsulating drugs, retaining more drugs, and having a low viscosity for the myocardial infarction (MI) injection. TheMI model was developed using SD rats injected under the skin with 85 mg/kg doxorubicin (DOX) for 2 days. The metabolic results showed that our AP-AD PNPs accelerated the blood flow in rats with MI, which increased the amounts of AP and AD in the circulatory system. This led to significant improvements in the cardiac index and lower amounts of AST, LDH, and CK in the blood. A histopathological study using Hematoxylin&eosin, and TUNEL staining showed that cardiac function had improved and apoptosis had decreased. Moreover, tests that checked the amounts of IL-6, TNF-α, NO, GSH, MDA, and SOD showed that AP-AD PNPs may help treat MI by reducing oxidative stress and inflammation, making it a potentially useful therapeutic approach. [ABSTRACT FROM AUTHOR]

Nanosatellites of CubeSat type due to, i.a., minimized costs of space missions, as well as the potential large application area, have become a significant part of the space economy sector recently. The opportunity to apply miniaturized microsystem (MEMS) tools in satellite space missions further accelerates both the space and the MEMS markets, which in the coming years are considered to become inseparable. As a response to the aforementioned perspectives, this paper presents a microfluidic mixer system for biological research to be conducted onboard CubeSat nanosatellites. As a high complexity of the space systems is not desired due to the need for failure-free and remotely controlled operation, the principal concept of the work was to design an entirely passive micromixer, based on lab-on-chip technologies. For the first time, the microfluidic mixer that uses inertial force generated by rocket engines during launch to the orbit is proposed to provide an appropriate mixing of liquid samples. Such a solution not only saves the space occupied by standard pumping systems, but also reduces the energy requirements, ultimately minimizing the number of battery modules and the whole CubeSat size. The structures of the microfluidic mixers were fabricated entirely out of biocompatible resins using MultiJet 3D printing technology. To verify the functionality of the passive mixing system, optical detection consisting of the array of blue LEDs and phototransistors was applied successfully. The performance of the device was tested utilizing an experimental rocket, as a part of the Spaceport America Cup 2023 competition. [ABSTRACT FROM AUTHOR]

Single cell methods have proliferated in recent years, made feasible by droplet microfluidic technologies, including commercialized technologies. Although the concept of single cell barcoding using these methodologies is straightforward, these assays require several assumptions about the underlying molecular biology for data interpretation. Following the initial droplet-based single cell demonstrations, new experimental and bioinformatics methods have evolved the baseline expectations of these assays, producing more complex and higher quality data, including single cell multi-omics. By generalizing themes from prior bioinformatics and experimental innovation, new users and experienced technology developers can identify opportunities to maximize data generation, improve analytical interpretation, and avoid failure modes in establishing new assays. Single cell sequencing technologies have become a fixture in the molecular profiling of cells due to their ease, flexibility, and commercial availability. In particular, partitioning individual cells inside oil droplets via microfluidic reactions enables transcriptomic or multi-omic measurements for thousands of cells in parallel. Complementing the multitude of biological discoveries from genomics analyses, the past decade has brought new capabilities from assay baselines to enable a deeper understanding of the complex data from single cell multi-omics. Here, we highlight four innovations that have improved the reliability and understanding of droplet microfluidic assays. We emphasize new developments that further orient principles of technology development and guidelines for the design, benchmarking, and implementation of new droplet-based methodologies. [ABSTRACT FROM AUTHOR]

Technologies for rapid and high-throughput separation of rare cells from large populations of other types of cells have recently attracted much attention in the field of bioengineering. Among the various cell separation technologies proposed in the past, dielectrophoresis has shown particular promise because of its preciseness of manipulation and noninvasiveness to cells. However, one drawback of dielectrophoresis devices is that their application of high voltage generates Joule heat that exposes the cells within the device to high temperatures. To further explore this problem, this study investigated the temperature field in a previously developed cell separation device in detail. The temperature rise at the bottom of the microfluidic channel in the device was measured using a micro-LIF method. Moreover, the thermofluidic behavior of the cell separation device was numerically investigated by adopting a heat generation model that takes the electric-field-dependent heat generation term into account in the energy equation. Under the operating conditions of the previously developed cell separation device, the experimentally obtained temperature rise in the device was approximately 20 °C, and the numerical simulation results generally agreed well. Next, parametric calculations were performed with changes in the flow rate of the cell sample solution and the solution conductivity, and a temperature increase of more than 40 °C was predicted. The results demonstrated that an increase in temperature within the cell separation device may have a significant impact on the physiological functions of the cells, depending on the operating conditions of the device. [ABSTRACT FROM AUTHOR]

Loop-Mediated Isothermal Loop-Mediated Isothermal Amplification (LAMP) is a widely used technique for nucleic acid amplification due to its high specificity, sensitivity, and rapid results. Advances in microfluidic lab-on-chip (LOC) technology have enabled the integration of LAMP into miniaturized devices, known as μ -LAMP, which require precise thermal control for optimal DNA amplification. This paper introduces a novel thermal bed design using PCB copper traces and F R − 4 dielectric materials, providing a reliable, modular, and repairable heating platform. The system achieves accurate and stable temperature control, which is critical for μ -LAMP applications, with temperature deviations within ±1.0 °C. The thermal bed's performance is validated through finite element method (FEM) simulations, showing uniform temperature distribution and a rapid thermal response of 2.5 s to reach the target temperature. These results highlight the system's potential for applications such as disease diagnostics, biological safety, and forensic analysis, where precision and reliability are paramount. [ABSTRACT FROM AUTHOR]

Simple Summary: This study compared a no-touch technique with conventional radical nephrectomy for the treatment of renal cell carcinoma in terms of circulating tumor cell (CTC) and circulating mesenchymal cell (CMC) release and patient prognosis. The results showed that the no-touch approach did not reduce CTC or CMC release or improve survival, suggesting that early pedicle ligation, the last standing Robson principle of radical nephrectomy, may have fallen. Nonetheless, the no-touch technique proved to be faster and as safe as the conventional radical nephrectomy. Healthy controls had no circulating cells; however, high CMC counts were found in chronic inflammation controls and oncocytoma patients, with no difference to RCC patients. Background: Circulating tumor cells (CTCs) may be the missing renal cell carcinoma (RCC) biomarker. No-touch (NT) resection has shown benefit in several tumors. Methods: A randomized controlled trial comparing CTC and circulating mesenchymal cell (CMC) release in no-touch (NT) vs. conventional (C) laparoscopic RN. Blood samples were collected at operation room arrival (S0), specimen extraction (S1), postoperative D1, and D30. CTCs were isolated and analyzed using RUBYchip™. Results: Thirty-four patients were included. No significant differences were found between groups in CTC and CMC counts, count variations between time points, complications, and survival. The total circulating cell detection rates in the NT, C, and overall RCC groups were 58.3%, 80.0%, and 70.4% at S0; 41.6%, 86.7%, and 66.7% at S1; 50.0%, 64.3%, and 60.0% at D1; and 54.5%, 42.9%, and 44.0% at D30, respectively. A progressive decrease in CMCs was observed in the C group after surgery, especially at D1 (4.78 to 1.64 CMCs/7.5 mL blood, p = 0.035). Healthy controls had no circulating cells; however, high CMC counts were found in chronic inflammation controls and oncocytoma patients, with no significant difference from RCC patients (p = 0.460). Conclusions: NT RN did not reduce circulating cell release nor improve survival compared to C RN. [ABSTRACT FROM AUTHOR]

Cell migration is a fundamental and functional cellular process, influenced by a complex microenvironment consisting of different cells and extracellular matrix. Recent research has highlighted that, besides biochemical cues from the microenvironment, physical cues can also greatly alter cellular behavior. However, due to the complexity of the microenvironment, little is known about how the physical interactions between migrating cells and surrounding microenvironment instructs cell movement. Here, we explore various examples of three-dimensional microenvironment reconstruction models in vitro and describe how the physical interplay between migrating cells and the neighboring microenvironment controls cell behavior. Understanding this mechanical cooperation will provide key insights into organ development, regeneration, and tumor metastasis. [ABSTRACT FROM AUTHOR]

Multiple iterations required to design ocular implants, which will last for the desired operational period of months or even years, necessitate the use of in-silico models for ocular drug delivery. In this study, we developed an in-silico model to simulate the flow of Aqueous Humor (AH) and drug delivery from an implant to the Trabecular Meshwork (TM). The implant, attached to the side of the intraocular lens (IOL), and the TM are treated as porous media, with their effects on AH flow accounted for using the Darcy equation. This model accurately predicts the physiological values of Intraocular Pressure (IOP) for both healthy individuals and glaucoma patients, as reported in the literature. Results reveal that the effective diffusivity of the drug within the implant is the critical parameter that can alter the bioavailability time period (BTP) from a few days to months. Intuitively, BTP should increase as effective diffusivity decreases. However, we discovered that with lower levels of initial drug loading, BTP declines when effective diffusivity falls below a specific threshold. Our findings further reveal that, while AH flow has a minimal effect on the drug release profile at the implant site, it significantly impacts drug availability at the TM. [Display omitted] • Developed an in-silico model that can simulate drug delivery from ocular implants. • Validated the predicted intra-ocular pressure values with the values reported in the literature. • For lower levels of loaded drug in the implant, bioavailability time period starts reducing as effective diffusivity is reduced below a certain threshold level. • Neglecting Aqueous Humor (AH) flow effects can result in substantially wrong predictions of drug availability at the Trabecular Meshwork. [ABSTRACT FROM AUTHOR]

The global outbreak of pathogen diseases has brought a huge risk to human lives and social development. Rapid diagnosis is the key strategy to fight against pathogen diseases. Development of detection methods and discovery of related affinity reagents are important parts of pathogen diagnosis. Conventional detection methods and affinity reagents discovery have some problems including much reagent consumption and labor intensity. Magnetic-based microfluidic chip integrates the unique advantages of magnetism and microfluidic technology, improving a powerful tool for pathogen detection and their affinity reagent discovery. This review provides a summary about the summary of pathogen detection through magnetic-based microfluidic chip, which refers to the pathogen nucleic acid detection (including extraction, amplification and signal acquisition), pathogen proteins and antibodies detection. Meanwhile, affinity reagents are served as the critical tool to specially capture pathogens. New affinity reagents are discovered to further facilitate the pathogen diagnosis. Microfluidic technology has also emerged as a powerful tool for affinity reagents discovery. Thus, this review further introduced the selection progress of aptamer as next generation affinity through the magnetic-based microfluidic technology. Using this selection technology shows great potential to improve selection performance, including integration and highly efficient selection. Finally, an outlook is given on how this field will develop on the basis of ongoing pathogen challenges. [ABSTRACT FROM AUTHOR]

Smart microgels have gained much attention because of their wide range of applications in the field of biomedical, environmental, nanotechnological and catalysis sciences. Most of the applications of microgels are strongly affected by their morphology, size and size distribution. Various methodologies have been adopted to obtain polymer microgel particles. Droplet microfluidic techniques have been widely reported for the fabrication of highly monodisperse microgel particles to be used for various applications. Monodisperse microgel particles of required size and morphology can be achieved via droplet microfluidic techniques by simple polymerization of monomers in the presence of suitable crosslinker or by gelation of high molecular weight polymers. This report gives recent research progress in fabrication, characterization, properties and applications of microgel particles synthesized by microfluidic methods. [ABSTRACT FROM AUTHOR]

Despite being extremely old concepts, plasmonics and surface plasmon resonance-based biosensors have been increasingly popular in the recent two decades due to the growing interest in nanooptics and are now of relevant significance in regards to applications associated with human health. Plasmonics integration into point-of-care devices for health surveillance has enabled significant levels of sensitivity and limit of detection to be achieved and has encouraged the expansion of the fields of study and market niches devoted to the creation of quick and incredibly sensitive label-free detection. The trend reflects in wearable plasmonic sensor development as well as point-of-care applications for widespread applications, demonstrating the potential impact of the new generation of plasmonic biosensors on human well-being through the concepts of personalized medicine and global health. In this context, the aim here is to discuss the potential, limitations, and opportunities for improvement that have arisen as a result of the integration of plasmonics into microsystems and lab-on-chip over the past five years. Recent applications of plasmonic biosensors in microsystems and sensor performance are analyzed. The final analysis focuses on the integration of microfluidics and lab-on-a-chip with quantum plasmonics technology prospecting it as a promising solution for chemical and biological sensing. Here it is underlined how the research in the field of quantum plasmonic sensing for biological applications has flourished over the past decade with the aim to overcome the limits given by quantum fluctuations and noise. The significant advances in nanophotonics, plasmonics and microsystems used to create increasingly effective biosensors would continue to benefit this field if harnessed properly. Advances in plasmonic biosensing are considered in relation to the last five years Plasmon-polariton excitation is analyzed with respect to its integration of microsystems Molecular and cellular applications are critically analyzed in terms of benefit/drawback of microsystems Quantum plasmonic biosensing and preliminary applications are discussed Research and market perspectives are analyzed with regard to plasmonics potentiality [ABSTRACT FROM AUTHOR]

STUDY QUESTION Can a functional in vitro model, containing the main cellular components of the uterine wall, be generated from cells derived from patient tissues? SUMMARY ANSWER We present a three-dimensional (3D) physiologically relevant, organ-on-a-chip model of the uterine wall containing primary endometrial and myometrial cellular participants, generated from human uterine tissue. WHAT IS KNOWN ALREADY As a highly dynamic reproductive organ, the human uterus plays fundamental physiological roles in menstruation and childbirth. The endometrial–myometrial junction (EMJ) defines the interface between the inner mucosal layer (endometrium) and outer smooth muscle zone (myometrium) that comprises the uterine wall. The EMJ is implicit in several uterine pathologies of unknown aetiology, including adenomyosis and abnormally invasive placenta; however, despite this, no patient-derived in vitro models of the uterine wall containing all EMJ participants currently exist. STUDY DESIGN, SIZE, DURATION We employed microfluidic technology to characterize multiple miniaturized models of the uterine wall. Protocols were tested that included variations in the seeding order of endometrial and myometrial fractions, and the addition of a low viscosity extracellular matrix to influence cell behaviour. Ultimately, functional hormone responses of patient-derived uterine wall models were assessed. PARTICIPANTS/MATERIALS, SETTING, METHODS Endometrial (n = 9) and myometrial biopsies (n = 4) were enzymatically dissociated to create epithelial, stromal and myometrial cellular fractions. Cell suspensions were seeded into non-adhesive poly(dimethylsiloxane) microfluidic devices containing 5 × 5 microwell arrays. The fate of individual cell types was monitored in real-time using fluorescent tracers, and cell phenotype was characterized by immunocytochemistry. Model functionality was assessed by measuring Ca2+ responses to agonist stimulation, and both insulin-like growth factor binding protein 1 (IGFBP-1) and osteopontin secretion in response to hormone stimulation. MAIN RESULTS AND THE ROLE OF CHANCE When subjected to microfluidic culture in isolation, endometrial stromal cells and smooth muscle myocytes formed compact spheroids, whilst epithelial cells produced diffuse aggregates. Tri-cultures were established by sequential seeding of individual or combined cell fractions at various ratios. Regardless of the protocol, epithelial cells localized to the outer periphery of tri-culture spheroids, which varied in morphology across the protocols. Incorporation of 5% [v/v] Matrigel® improved the reproducibility of 3D aggregates which exhibited robust self-assembly of a stromal/smooth muscle core encased in epithelium. Exposure of tri-cultures to oestradiol, medroxyprogesterone acetate and cyclic adenosine monophosphate (cAMP) increased secretion of IGFBP-1, which indicates stromal decidualization, and enhanced epithelial cell osteopontin secretion. Stimulation with endothelin-1 induced Ca2+ signalling in myocytes. LIMITATIONS, REASONS FOR CAUTION Endometrial and myometrial tissue was collected from relatively few donors. Myometrial tissue was collected from pregnant donors, which may have influenced the myocyte phenotype. Furthermore, endometrial tissue sampling was from women not having a hysterectomy, thus may not include the deeper basalis region, which may limit the physiological mimicry of the final models. WIDER IMPLICATIONS OF THE FINDINGS Our novel approach to modelling the uterine wall in 3D captures all of the main cell types in a medium-throughput system, enabling the screening of hundreds of cultures in parallel from a single biopsy. This system shows great promise for examining the cellular interplay between physiological cues and EMJ pathologies, such as the impact of uterine peristalsis and cyclical hormones on the pathogenesis of adenomyosis. STUDY FUNDING/COMPETING INTEREST(S) C.B. was supported by an Organ-on-a-Chip Technologies Network Pump Priming Project grant. C.J.H. was supported by a Wellbeing of Women project grant (RG2137), SRI/Bayer and Wellcome Trust IFFS3. D.K.H. was supported by a Wellbeing of Women project grant (RG2137) and MRC clinical research training fellowship (MR/V007238/1). M.Z. is Director and Co-Founder of ScreenIn3D Limited. The other authors declare no conflict of interest. TRIAL REGISTRATION NUMBER N/A. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles (MNPs) have garnered significant attention in biomedical applications. Due to their large surface area and tunable properties, MNPs are used in microfluidic systems, which allow for the manipulation and control of fluids at micro- or nanoscale. Using microfluidic systems allows for a faster, less expensive, and more efficient approach to applications like bioanalysis. MNPs in microfluidics can precisely identify and detect bioanalytes on a single chip by controlling analytes in conjunction with magnetic particles (MPs) and separating various particles for analytical functions at the micro- and nanoscales. Numerous uses for these instruments, including cell-based research, proteomics, and diagnostics, have been reported. The successful reduction in the size of analytical assays and the creation of compact LOC platforms have been made possible with the assistance of microfluidics. Microfluidics is a highly effective method for manipulating fluids as a continuous flow or discrete droplets. Since the implementation of the LOC technology, various microfluidic methods have been developed to improve the efficiency and precision of sorting, separating, or isolating cells or microparticles from their original samples. These techniques aim to surpass traditional laboratory procedures. This review focuses on the recent progress in utilizing microfluidic systems that incorporate MNPs for biological applications. [ABSTRACT FROM AUTHOR]

Microfluidic devices have been the subject of considerable attention in recent years. The development of novel microfluidic devices, their evaluation, and their validation requires simulations. While common methods based on Computational Fluid Dynamics (CFD) can be time-consuming, 1D simulation provides an appealing alternative that leads to efficient results with reasonable quality. Current 1D simulation tools cover specific microfluidic applications; however, these tools are still rare and not widely adopted. There is a need for a more versatile and adaptable tool that covers novel applications, like mixing and the addition of membranes, and allows easy extension, resulting in one comprehensive 1D simulation tool for microfluidic devices. In this work, we present an open-source, modular, and extendable 1D simulation approach for microfluidic devices, which is available as an open-source software package at https://github.com/cda-tum/mmft-modular-1D-simulator. To this end, we propose an implementation that consists of a base module (providing the core functionality) that can be extended with dedicated application-specific modules (providing dedicated support for common microfluidic applications such as mixing, droplets, membranes, etc.). Case studies show that this indeed allows to efficiently simulate a broad spectrum of microfluidic applications in a quality that matches previous results or even fabricated devices. [ABSTRACT FROM AUTHOR]

Plant-based biotechnology is crucial for developing renewable biofuels, enhancing bioremediation, and improving the food supply chain. Modern agricultural technologies often face limitations due to variable weather conditions and significant infrastructure costs. Addressing these challenges, smaller-scale biotechnologies optimize plant production through controlled lighting and nutrient supply, mitigating the impact of adverse weather. In vitro technologies are particularly effective for promoting plant growth with desirable phenotypic traits under controlled conditions, though they bring challenges related to sustainability and costs. Recent innovations in microfabrication have led to the miniaturization of traditional in vitro technologies, significantly reducing both sample volumes and costs. This review explores the advancements in microfluidic systems for plant studies, covering a range from single plant cells to mature plants, and discusses the common materials and integrated technologies employed in microfabrication for in-depth in vitro studies. • Small-scale biotechnologies address agricultural problems. • Single-plant cell positioning and observation are possible with microfluidics. • Miniaturized Optimized in vitro conditions improve plant development. • Advanced miniaturized in vitro technology reduced sample volume and cost. • Plant research uses microfluidics for macro and micro inspection. [ABSTRACT FROM AUTHOR]

Controlled manufacturing and long-term stability are key challenges in the development and translation of nanomedicines. This is exemplified by the mRNA-nanoparticle vaccines against COVID-19, which require (ultra-)cold temperatures for storage and shipment. Various cryogenic protocols have been explored to prolong nanomedicine shelf-life. However, freezing typically induces high mechanical stress on nanoparticles, resulting in aggregation or destabilization, thereby limiting their performance and application. Hence, evaluating the impact of freezing and storing on nanoparticle properties already early-on during preclinical development is crucial. In the present study, we used prototypic π electron-stabilized polymeric micelles based on mPEG- b -p(HPMAm-Bz) block copolymers to macro- and microscopically study the effect of different cryoprotective excipients on nanoformulation properties like size and size distribution, as well as on freezing-induced aggregation phenomena via in-situ freezing microscopy. We show that sucrose, unlike trehalose, efficiently cryoprotected paclitaxel-loaded micelles, and we exemplify the impact of formulation composition for efficient cryoprotection. We finally establish microfluidic mixing to formulate paclitaxel-loaded micelles with sucrose as a cryoprotective excipient in a single production step and demonstrate their stability for 6 months at −20 °C. The pharmaceutical properties and preclinical performance (in terms of tolerability and tumor growth inhibition in a patient-derived triple-negative breast cancer xenograft mouse model) of paclitaxel-loaded micelles were successfully cryopreserved. Together, our efforts promote future pharmaceutical development and translation of π electron-stabilized polymeric micelles, and they illustrate the importance of considering manufacturing and storage stability issues early-on during nanomedicine development. [Display omitted] [ABSTRACT FROM AUTHOR]

The aim of this research is to validate a new prototyping method for microfluidic devices which could compete with the widely used polydimethylsiloxane soft lithography. This alternative methodology uses laser‐etched glass and pre‐cured silicone as main materials. A dual approach is chosen for validation, testing prototypes of a mixing device well known in the scientific literature. Specifically the focus is to evaluate the mixing efficiency (ME) of two fluids flowing through the device. After fine‐tuning the fabrication process, the ME is experimentally evaluated, and the results are compared with a 3D computational fluid dynamic analysis. [ABSTRACT FROM AUTHOR]

High-throughput screening techniques are pivotal to unlocking the mysteries of biology. Yet, the promise of droplet microfluidics in enabling single-cell resolution, ultra-high-throughput screening remains largely unfulfilled. Droplet sorting errors caused by polydisperse droplet sizes that are often inevitable in multi-step assays have severely limited the effectiveness and utility of this technique, especially when screening large libraries. Even a relatively low 1% sorting error results in 10,000 false calls in a 1,000,000 droplet screen, imposing an unreasonably large burden on downstream validation. Here, we present NOVAsort (Next-generation Opto-Volume-based Accurate droplet sorter), a device capable of discerning droplets based on both size and fluorescence intensity. With a 1000- and 10,000-fold reduction in false positives and false negatives, respectively. NOVAsort addresses the challenges of conventional droplet sorting approaches and sets standards for accuracy and throughput in droplet microfluidic assays. Droplet microfluidic tools with single-cell resolution and high-throughput screening capacities remain scarce. Here, the authors propose NOVAsort, a next-generation droplet sorter that can discern droplets based on both size and fluorescence, which can overcome common problems with conventional sorters. [ABSTRACT FROM AUTHOR]

Diabetes currently affects approximately 500 million people worldwide and is one of the most common causes of mortality in the United States. To diagnose and monitor diabetes, finger-prick blood glucose testing has long been used as the clinical gold standard. For diabetes treatment, insulin is typically delivered subcutaneously through cannula-based syringes, pens, or pumps in almost all type 1 diabetic (T1D) patients and some type 2 diabetic (T2D) patients. These painful, invasive approaches can cause non-adherence to glucose testing and insulin therapy. To address these problems, researchers have developed miniaturized blood glucose testing devices as well as microfluidic platforms for non-invasive glucose testing through other body fluids. In addition, glycated hemoglobin (HbA1c), insulin levels, and cellular biomechanics-related metrics have also been considered for microfluidic-based diabetes diagnosis. For the treatment of diabetes, insulin has been delivered transdermally through microdevices, mostly through microneedle array-based, minimally invasive injections. Researchers have also developed microfluidic platforms for oral, intraperitoneal, and inhalation-based delivery of insulin. For T2D patients, metformin, glucagon-like peptide 1 (GLP-1), and GLP-1 receptor agonists have also been delivered using microfluidic technologies. Thus far, clinical studies have been widely performed on microfluidic-based diabetes monitoring, especially glucose sensing, yet technologies for the delivery of insulin and other drugs to diabetic patients with microfluidics are still mostly in the preclinical stage. This article provides a concise review of the role of microfluidic devices in the diagnosis and monitoring of diabetes, as well as the delivery of pharmaceuticals to treat diabetes using microfluidic technologies in the recent literature. [ABSTRACT FROM AUTHOR]

It was the aim of this study to design charge converting lipid nanoparticles (LNP) via a microfluidic mixing technique used for the preparation and coating of LNP. LNP consisting of 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), cholesterol, N-(carbonyl-methoxypolyethyleneglycol-2000)-1,2-distearoyl-sn-glycero-3-phosphoethanolamine (MPEG-2000-DSPE), and various cationic surfactants were prepared at diverging flow rate ratios (FRR) via microfluidic mixing. Utilizing a second chip in the microfluidic set-up, LNP were coated with polyoxyethylene (9) nonylphenol monophosphate ester (PNPP). LNP were examined for their stability in different physiologically relevant media as well as for hemolytic and cytotoxic effects. Finally, phosphate release and charge conversion of PNPP-coated LNP were evaluated after incubation with alkaline phosphatase and on Caco2-cells. LNP produced at an FRR of 5:1 exhibited a size between 80 and 150 nm and a positive zeta potential. Coating with PNPP within the second chip led to LNP exhibiting a negative zeta potential. After incubation with 1 U/ml alkaline phosphatase for 4 h, zeta potential of the LNP containing 1,2-dioleoyloxy-3-trimethylammonium-propane chloride (DOTAP) as cationic component shifted from − 35 mV to approximately + 5 mV. LNP prepared with other cationic surfactants remained slightly negative after enzymatic phosphate cleavage. Manufacturing of LNP containing PNPP and DOTAP via connection of two chips in a microfluidic instrument proves to show efficient change in zeta potential from negative to positive after incubation with alkaline phosphatase. [ABSTRACT FROM AUTHOR]

Microfluidics is widely regarded as a leading technology for industrial-scale manufacture of multicomponent, gene-based nanomedicines in a reproducible manner. Yet, very few investigations detail the impact of flow conditions on the biological performance of the product, particularly biocompatibility and therapeutic efficiency. Herein, this study investigated the engineering of a novel lipid-Eudragit hybrid nanoparticle in a bifurcating microfluidics micromixer for plasmid DNA (pDNA) delivery. Nanoparticles of ~150 nm in size, with uniform polydispersity index (PDI = 0.2) and ξ-potential of 5–11 mV were formed across flow rate ratios (FRR, aqueous to organic phase) of 3:1 and 5:1, respectively. The hybrid nanoparticles maintained colloidal stability and structural integrity of loaded pDNA following recovery by ultracentrifugation. Importantly, in vitro testing in human embryonic kidney cell line (HEK293T) revealed significant differences in biocompatibility and transfection efficiency (TE). Lipid-Eudragit nanoparticles produced at FRR 3:1 displayed high cellular toxicity (0–30% viability), compared with nanoparticles prepared at FRR 5:1 (50–100% viability). Red fluorescent protein (RFP) expression was sustained for 24–72 h following exposure of cells to nanoparticles, indicating controlled release of pDNA and trafficking to the nucleus. Nanoparticles produced at FRR 5:1 resulted in markedly higher TE (12%) compared with those prepared at FRR 3:1 (2%). Notably, nanoparticles produced using the bench-scale nanoprecipitation method resulted in lower biocompatibility (30–90%) but higher RFP expression (25–38%). These findings emphasize the need for in-depth analysis of the effect of formulation and flow conditions on the physicochemical and biological performance of gene nanomedicines when transitioning from bench to clinic. Transitioning lipid-Eudragit hybrid nanoparticles from bench-scale nanoprecipitation to industrial-scale microfluidics [ABSTRACT FROM AUTHOR]

Immunotherapies are a revolutionary approach to treating cancer by utilizing the body's immune system to target and combat cancer cells. This approach offers promising alternatives to traditional chemotherapies. Its potential to induce long-lasting remissions and specificity for cancer cells, which minimizes side effects, makes it a cutting-edge treatment with tremendous potential. With the increase of the clinical usage of immunotherapy, evidence emerges of the microbiome's impact on both tumor growth and response to immunotherapy. The proposed involvement of the microbiome can change treatment efficacy by altering drug metabolism and reshaping the immune system response. Understanding the specific interactions between tumor cells, immune cells, and the microbiome is a critical step in the advancement of immunotherapy. To study the complex interaction between cancer immunity and the microbiome, various preclinical in vivo and in vitro models have been developed. We have recently described the use of an ex vivo preclinical model for anti-cancer treatment outcome prediction -tumor tissue equivalents (organoids). Specifically, immune-reactive tumor organoids are proposed as a novel tool for understanding how the microbiome influences cancer immunity and immunotherapy. More importantly, this platform can utilize patient samples to dissect patient-specific elements regulating cancer immune response and microbiome influence. This review presents the rationale for using the immunereactive tumor organoids model to study the interactions between the microbiome and cancer immunotherapy. It will discuss available components of the model and analyze their interplay, summarize relevant experimental data, and assess their validity. Additionally, it explores the potential of immune-reactive organoids for personalized treatment approaches. Understanding the microbiome's role in immunotherapy outcomes will lead to transformative cancer treatment via a simple change of diet or other microbiome manipulations. Ongoing research on microbiome-cancer interactions utilizing the described model systems will lead to innovative treatment strategies and improved patient outcomes. [ABSTRACT FROM AUTHOR]

AbstractGiant liposomes, or giant unilamellar vesicles (GUVs), have been utilized as cell-size bioreactors to replicate the physical and chemical properties of biological cells. However, conventional methods for preparing GUVs typically lack precise control over their size. Several research groups have recently developed microfluidic techniques to create monodisperse GUVs by generating water-in-oil-in-water (W/O/W) droplets with a thin oil layer that subsequently transform into GUVs. However, the formation of a thin oil shell requires the intricate control of the flow rate, which can be both challenging and unstable. In this study, we investigated the design of a two-step flow-focusing microfluidic channel to produce stable W/O/W droplets. These droplets underwent substantial oil layer reduction through spontaneous removal by fluidic shear forces. Consequently, the majority of the oil layer in the W/O/W droplets was reduced, improving uniformity of GUVs. [ABSTRACT FROM AUTHOR]

Cytokines, crucial in immune modulation, impact disease progression when their secretion is dysregulated. Existing methods for profiling cytokine secretion suffer from time‐consuming and labor‐intensive processes and often fail to capture the dynamic nature of immune responses. Here, iSECRETE, an integrated platform that enables synchronous cell activation, wash‐free, and target‐responsive protein detection for single‐cell IFN‐γ cytokine secretion analysis within 30 min at room temperature is presented. By incorporating a DNA proximity assay (DPA) into a multifunctional microfluidic system, one‐pot homogenous cytokine signal amplification, with a limit of detection of ≈50 secreted molecules per cell is achieved. iSECRETE can robustly handle various sample types that are shown. Two distinct immune activation assay modalities are demonstrated on iSECRETE. Finally, the detection of single‐cell IFN‐γ secretion as an activation hallmark of chimeric antigen receptor T cells within 6 h of exposure to cancer targets is shown. iSECRETE represents the fastest single‐cell sample‐to‐result cytokine secretion assay to date, providing a powerful tool for advancing the understanding of biological phenotypes, functions, and pathways under in vivo‐like conditions. [ABSTRACT FROM AUTHOR]

Interactions between carbon nanotubes (CNTs) and fluid flows are central to the operation of several emerging nanotechnologies. In this paper, we explore the fluid-structure interaction of CNT micropillars in wall-bounded shear flows, relevant to recently developed microscale wall shear stress sensors. We monitor the deformation of CNT micropillars in channel flow as the flow rate and wall shear stress are gradually varied. We quantify how the micropillars bend at low wall shear stress, and then will commonly tilt abruptly from their base above a threshold wall shear stress, which is attributed to the lower density of the micropillars in this region. Some micropillars are observed to flutter rapidly between a vertical and horizontal position around this threshold wall shear stress, before settling to a tilted position as wall shear stress increases further. Tilted micropillars are found to kink sharply near their base, similar to the observed buckling near the base of CNT micropillars in compression. Upon reducing the flow rate, micropillars are found to fully recover from a near horizontal position to a near vertical position, even with repeated on–off cycling. At sufficiently high wall shear stress, the micropillars were found to detach at the catalyst particle-substrate interface. The mechanical response of CNT micropillars in airflow revealed by this study provides a basis for future development efforts and the accurate simulation of CNT micropillar wall shear stress sensors. [ABSTRACT FROM AUTHOR]

Although micron‐sized microgels have become important building blocks in regenerative materials, offering decisive interactions with living matter, their chemical composition mostly significantly varies when their network morphology is tuned. Since cell behavior is simultaneously affected by the physical, chemical, and structural properties of the gel network, microgels with variable morphology but chemical equivalence are of interest. This work describes a new method to produce thermoresponsive microgels with defined mechanical properties, surface morphologies, and volume phase transition temperatures. A wide variety of microgels is synthesized by crosslinking monomers or star polymers at different temperatures using thermally assisted microfluidics. The diversification of microgels with different network structures and morphologies but of chemical equivalence offers a new platform of microgel building blocks with the ability to undergo phase transition at physiological temperatures. The method holds high potential to create soft and dynamic materials while maintaining the chemical composition for a wide variety of applications in biomedicine. [ABSTRACT FROM AUTHOR]