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Search indexed bioRxiv preprints in genomics, neuroscience, cell biology and bioinformatics. Read source abstracts and check manuscript versions; preprints are not peer reviewed.

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At least 217 records · Page 12Linked to original sources
bioRxiv2017

PERFORMANCE OF AN AMBULATORY DRY-EEG DEVICE FOR AUDITORY CLOSED-LOOP STIMULATIONS IN THE HOME ENVIRONMENT

ObjectiveRecent research has shown that auditory closed-loop stimulations can enhance sleep slow oscillations (SO) to improve N3 sleep quality and cognition. Previous studies have been conducted in a lab environment and on a small sample size. The present study aimed at validating and assessing the performance of a novel ambulatory wireless dry-EEG device (WDD), for auditory closed-loop stimulations of SO during N3 sleep at home.\n\nMaterial and MethodsThe performance of the WDD to detect N3 sleep automatically and to send auditory closed-loop stimulations on SO were tested on 20 young healthy subjects who slept with both the WDD and a miniaturized polysomnography (part 1) in both stimulated and sham nights within a double blind, randomized and crossover design.\n\nThe electrophysiological effects of auditory closed-loop stimulation on delta power increase were assessed after 1 and 10 nights of stimulations on an observational pilot study in the home environment including 90 middle-aged subjects (part 2).\n\nResultsThe sensitivity and specificity of the WDD to automatically detect N3 sleep in real-time were 0.70 and 0.90, respectively. The stimulation accuracy of the SO ascending-phase targeting was 45{+/-}52{degrees}. The stimulation protocol induced an increase of 39.5 % of delta power after the stimulations. The increase of SO response to auditory stimulations remained at the same level after 10 consecutive nights.\n\nConclusionThe WDD shows good performances to automatically detect in real-time N3 sleep and to send auditory closed-loop stimulations on SO accurately. These stimulations increased the SO amplitude during N3 sleep without any adaptation effect after 10 consecutive nights. This tool provides new perspectives to figure out novel sleep EEG biomarkers in longitudinal studies and can be interesting to conduct broad studies on the effects of auditory stimulations during sleep.

bioengineering↗
bioRxiv2017

Single-shot super-resolution total internal reflection fluorescence microscopy

We demonstrate a simple method for combining instant structured illumination microscopy (SIM) with total internal reflection fluorescence microscopy (TIRF), doubling the spatial resolution of TIRF (down to 115 +/-13 nm) and enabling imaging frame rates up to 100 Hz over hundreds of time points. We apply instant TIRF-SIM to multiple live samples, achieving rapid, high contrast super-resolution imaging in close proximity to the coverslip surface.

bioengineering↗
bioRxiv2017

Adeno-associated virus mediated gene delivery: Implications for scalable in vitro and in vivo cardiac optogenetic models

AimsAdeno-associated viruses (AAVs) provide advantages in long-term, cardiac-specific gene expression. However, AAV serotype specificity data is lacking in cardiac models relevant to optogenetics. We aimed to identify the optimal AAV serotype (1, 6, or 9) in pursuit of scalable rodent and human models for cardiac optogenetics and elucidate the mechanism of virus uptake.\n\nMethodsIn vitro syncytia of primary neonatal rat ventricular cardiomyocytes (NRVMs) and human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) were infected with AAVs 1, 6, and 9 containing the transgene for eGFP or channelrhodopsin-2 (ChR2) fused to mCherry. In vivo adult rats were intravenously injected with AAV1 and 9 containing ChR2-mCherry.\n\nResultsTransgene expression profiles of rat and human cells in vitro revealed that AAV1 and 6 significantly outperformed AAV9. In contrast, systemic delivery of AAV9 in adult rat hearts yielded significantly higher levels of ChR2-mCherry expression and optogenetic responsiveness. We tracked the mechanism of virus uptake to purported receptor-mediators for AAV 1/6 (cell surface sialic acid) and AAV9(37/67kDa laminin receptor, LamR). In vitro desialylation of NRVMs and hiPSC-CMs with neuraminidase significantly decreased AAV1,6-mediated gene expression, but interestingly, desialylation of hiPSC-CMs increased AAV9-mediated expression. In fact, only very high viral doses of AAV9-ChR2-mCherry, combined with neuraminidase treatment yielded consistent optogenetic responsiveness in hiPSC-CMs. Differences between the in vitro and in vivo performance of AAV9 could be correlated to robust LamR expression in the adult and neonatal rat hearts, but no expression in vitro in cultured cells. The dynamic nature of LamR expression and its dependence on environmental factors was further corroborated in intact adult human ventricular tissue slices.\n\nConclusionThe combined transgene expression and cell surface receptor data may explain the preferential efficiency of AAV1/6 in vitro and AAV9 in vivo for cardiac delivery and mechanistic knowledge of their action can help guide cardiac optogenetic efforts.

bioengineering↗
bioRxiv2017

Rosetta Antibody Design (RAbD): A General Framework for Computational Antibody Design

A structural-bioinformatics-based computational methodology and framework have been developed for the design of antibodies to targets of interest. RosettaAntibodyDesign (RAbD) samples the diverse sequence, structure, and binding space of an antibody to an antigen in highly customizable protocols for the design of antibodies in a broad range of applications. The program samples antibody sequences and structures by grafting structures from a widely accepted set of the canonical clusters of CDRs (North et al., J. Mol. Biol., 406:228-256, 2011). It then performs sequence design according to amino acid sequence profiles of each cluster, and samples CDR backbones using a flexible-backbone design protocol incorporating cluster-based CDR constraints. Starting from an existing experimental or computationally modeled antigen-antibody structure, RAbD can be used to redesign a single CDR or multiple CDRs with loops of different length, conformation, and sequence. We rigorously benchmarked RAbD on a set of 60 diverse antibody-antigen complexes, using two design strategies - optimizing total Rosetta energy and optimizing interface energy alone. We utilized two novel metrics for measuring success in computational protein design. The design risk ratio (DRR) is equal to the frequency of recovery of native CDR lengths and clusters divided by the frequency of sampling of those features during the Monte Carlo design procedure. Ratios greater than 1.0 indicate that the design process is picking out the native more frequently than expected from their sampled rate. We achieved DRRs for the non-H3 CDRs of between 2.4 and 4.0. The antigen risk ratio (ARR) is the ratio of frequencies of the native amino acid types, CDR lengths, and clusters in the output decoys for simulations performed in the presence and absence of the antigen. For CDRs, we achieved cluster ARRs as high as 2.5 for L1 and 1.5 for H2. For sequence design simulations without CDR grafting, the overall recovery for the native amino acid types for residues that contact the antigen in the native structures was 72% in simulations performed in the presence of the antigen and 48% in simulations performed without the antigen, for an ARR of 1.5. For the non-contacting residues, the ARR was 1.08. This shows that the sequence profiles are able to maintain the amino acid types of these conserved, buried sites, while recovery of the exposed, contacting residues requires the presence of the antigen-antibody interface. We tested RAbD experimentally on both a lambda and kappa antibody-antigen complex, successfully improving their affinities 10 to 50 fold by replacing individual CDRs of the native antibody with new CDR lengths and clusters.\n\nAuthor SummaryAntibodies are proteins produced by the immune system to attack infections and cancer and are also used as drugs to treat cancer and autoimmune diseases. The mechanism that has evolved to produce them is able to make 10s of millions of different antibodies, each with a different surface used to bind the foreign or mutated molecule. We have developed a method to design antibodies computationally, based on the 1000s of experimentally determined three-dimensional structures of antibodies available. The method works by treating pieces of these structures as a collection of parts that can be combined in new ways to make better antibodies. Our method has been implemented in the protein modeling program Rosetta, and is called RosettaAntibodyDesign (RAbD). We tested RAbD both computationally and experimentally. The experimental test shows that we can improve existing antibodies by 10 to 50 fold, paving the way for design of entirely new antibodies in the future.

bioengineering↗
bioRxiv2017

Compact Standalone Platform for Neural Recording with Real-Time Spike Sorting and Data Logging

ObjectiveLongitudinal observation of single unit neural activity from large numbers of cortical neurons in awake and mobile animals is often a vital step in studying neural network behaviour and towards the prospect of building effective Brain Machine Interfaces (BMIs). These recordings generate enormous amounts of data for transmission & storage, and typically require offline processing to tease out the behaviour of individual neurons. Our aim was to create a compact system capable of: 1) reducing the data bandwidth by circa 3 orders of magnitude (greatly improving battery lifetime and enabling low power wireless transmission); 2) producing real-time, low-latency, spike sorted data; and 3) long term untethered operation. Approach. We have developed a headstage that operates in two phases. In the short training phase a computer is attached and classic spike sorting is performed to generate templates. In the second phase the system is untethered and performs template matching to create an event driven spike output that is logged to a micro-SD card. To enable validation the system is capable of logging the high bandwidth raw neural signal data as well as the spike sorted data. Main results. The system can successfully record 32 channels of raw neural signal data and/or spike sorted events for well over 24 hours at a time and is robust to power dropouts during battery changes as well as SD card replacement. A 24-hour initial recording in a non-human primate M1 showed consistent spike shapes with the expected changes in neural activity during awake behaviour and sleep cycles. Significance The presented platform allows neural activity to be unobtrusively monitored and processed in real-time in freely behaving untethered animals revealing insights that are not attainable through scheduled recording sessions and provides a robust, low-latency, low-bandwidth output suitable for BMIs, closed loop neuromodulation, wireless transmission and long term data logging.

bioengineering↗
bioRxiv2018

Cas-CLIP: a method for customizing pooled CRISPR libraries

ABSCTRACTAlthough pooled CRISPR libraries are widely used in high-throughput screening to study various biological processes, library construction for researchers own study is a time-consuming, labor-intensive, and expensive process. In this study, we develop a simple, scalable method, called Cas-CLIP, to customize conventional pooled CRISPR libraries using the CRISPR/Cas9 system. We show that conventional pooled CRISPR libraries can be modified by eliminating gRNAs that target positive genes, enabling the identification of unknown target genes in CRISPR screening. Cas-CLIP is a precise method for customizing conventional pooled CRISPR libraries and will broaden the scope of high-throughput screening technology.

bioengineering↗
bioRxiv2017

Crossing enhanced and high fidelity SpCas9 nucleases to optimize specificity and cleavage

BackgroundThe propensity for off-target activity of Streptococcus pyogenes Cas9 (SpCas9) has been considerably decreased by rationally engineered variants with increased fidelity (eSpCas9; SpCas9-HF1). However, a subset of targets still generate considerable off-target effects. To deal specifically with these targets, we generated new \"Highly enhanced Fidelity\" nuclease variants (HeFSpCas9s) containing mutations from both eSpCas9 and SpCas9-HF1 and examined these improved nuclease variants side-by-side, to decipher the factors that affect their specificities and to determine the optimal nuclease for applications sensitive to off-target effects.\n\nResultsThese three increased-fidelity nucleases can routinely be used only with perfectly matching 20 nucleotide-long spacers; a matching 5' G extension being more detrimental to their activities than a mismatching one. HeFSpCas9s exhibit substantially improved specificity specifically for those targets for which eSpCas9 and SpCas9-HF1 have higher off-target propensity. There is also a ranking among the targets by their cleavability and off-target effects manifested by the increased fidelity nucleases. Furthermore, we show that the mutations in these variants may diminish the cleavage, but not the DNA-binding, of SpCas9s.\n\nConclusionsNo single nuclease variant shows generally superior fidelity; instead, for highest specificity cleavage, each target needs to be matched with an appropriate high fidelity nuclease. We provide here a framework for generating new nuclease variants for targets that currently have no matching optimal nuclease, and offer a simple mean for identifying the optimal nuclease for targets in the absence of accurate target-ranking prediction tools.

bioengineering↗
bioRxiv2017

Data-driven Modeling of Thrombus Size and Shape in Aortic Dissections: Role of Hemodynamics

Aortic dissection is a pathology that manifests due to micro-structural defects in the aortic wall. Blood enters the damaged wall through an intimal tear, thereby creating a so-called false lumen and exposing the blood to thrombogenic intramural constituents such as collagen. The natural history of this acute vascular injury thus depends, in part, on thrombus formation, maturation, and possible healing within the false lumen. A key question is: Why do some false lumens thrombose completely while other thrombose partially or little at all? An ability to predict the location and extent of thrombus in subjects with dissection could contribute significantly to clinical decision-making, including interventional design. We develop, for the first time, a data-driven particle-continuum model for thrombus formation in a murine model of aortic dissection. In the proposed model, we simulate a final-value problem in lieu of the original initial-value problem with significantly fewer particles that may grow in size upon activation, representing the local concentration of blood-borne species. Numerical results confirm that geometry and local hemodynamics play significant roles in the acute progression of thrombus. Despite geometrical differences between murine and human dissections, mouse models can provide considerable insight and have gained in popularity owing to their reproducibility. Our results for three classes of geometrically different false lumens show that thrombus forms and extends to a greater extent in regions with lower bulk shear rates. Dense thrombi are less likely to form in high-shear zones and in the presence of strong vortices. The present data-driven study suggests that the proposed model is robust and can be employed to assess thrombus formation in human aortic dissections.

bioengineering↗
bioRxiv2017

Systemic and vascular inflammation in an in-vitro model of central obesity

Metabolic disorders due to over-nutrition are a major global health problem, often associated with obesity and related morbidities. Obesity is peculiar to humans, as it is associated with lifestyle and diet, and so difficult to reproduce in animal models.\n\nHere we describe a model of human central adiposity based on a 3-tissue system consisting of a series of interconnected fluidic modules. Given the causal link between obesity and systemic inflammation, we focused primarily on pro-inflammatory markers, examining the similarities and differences between the 3-tissue model and evidence from human studies in the literature. When challenged with high levels of adiposity, the in-vitro system manifests cardiovascular stress through expression of E-selectin and von Willebrand factor as well as systemic inflammation (expressing IL-6 and MCP-1) as observed in humans. Interestingly, most of the responses are dependent on the synergic interaction between adiposity and the presence of multiple tissue types. The set-up has the potential to reduce animal experiments in obesity research and may help unravel specific cellular mechanisms which underlie tissue response to nutritional overload.

bioengineering↗
bioRxiv2017

Controller for microfluidic large-scale integration

Microfluidic devices with integrated valves provide precise, programmable fluid handling platforms for high-throughput biological or chemical assays. However, setting up the infrastructure to control such platforms often requires specific engineering expertise or expensive commercial solutions. To address these obstacles, we present a Kit for Arduino-based Transistor Array Actuation (KATARA), an open-source and low-cost Arduino-based controller that can drive 70 solenoid valves to pneumatically actuate integrated microfluidic valves. We include a python package with a GUI to control the KATARA from a personal computer. No programming experience is required.

bioengineering↗
bioRxiv2017

The Role Of Circle Of Willis Anatomy Variations In Cardio-embolic Stroke - A Patient-specific Simulation Based Study.

We describe a patient-specific simulation based investigation on the role of Circle of Willis anatomy in cardioembolic stroke. Our simulation framework consists of medical image-driven modeling of patient anatomy including the Circle, 3D blood flow simulation through patient vasculature, embolus transport modeling using a discrete particle dynamics technique, and a sampling based approach to incorporate parametric variations. A total of 24 (four patients and six Circle anatomies including the complete Circle) models were considered, with cardiogenic emboli of varying sizes and compositions released virtually and tracked to compute distribution to the brain. The results establish that Circle anatomical variations significantly influence embolus distribution to the six major cerebral arteries. Embolus distribution to MCA territory is found to be least sensitive to the influence of anatomical variations. For varying Circle topologies, differences in flow through cervical vasculature are observed. This incoming flow is recruited differently across the communicating arteries of the Circle for varying anastomoses. Emboli interact with the routed flow, and can undergo significant traversal across the Circle arterial segments, depending upon their inertia and density ratio with respect to blood. This interaction drives the underlying biomechanics of embolus transport across the Circle, explaining how Circle anatomy influences embolism risk.

bioengineering↗
bioRxiv2017

Effects of mechanical loading on cortical defect repair using a novel mechanobiological model of bone healing

Mechanical loading is an important aspect of post-surgical care. The timing of load application relative to the injury event is thought to differentially regulate repair depending on the stage of healing. Here, we show using a novel mechanobiological model of cortical defect repair that daily loading (5 N peak load, 2 Hz, 60 cycles, 4 consecutive days) during hematoma consolidation and inflammation disrupts the injury site and activates cartilage formation on the periosteal surface adjacent to the defect. We also show that daily loading during the matrix deposition phase enhances both bone and cartilage formation at the defect site, while loading during the remodeling phase results in an enlarged woven bone regenerate. All loading regimens resulted in abundant cellular proliferation within the regenerate and at the periosteal surface and fibrous tissue formation directly above the defect. Stress was concentrated at the edges of the defect during exogenous loading, and finite element (FE)-modeled longitudinal strain ({varepsilon}zz) values along the anterior and posterior borders of the defect (~2200 {varepsilon}) were an order of magnitude larger than strain values on the proximal and distal borders (~50-100 {varepsilon}). These findings demonstrate that all phases of cortical defect healing are sensitive to physical stimulation. In addition, the proposed novel mechanobiological model offers several advantages including its technical simplicity and its well-characterized and spatially confined repair program, making effects of physical and biological interventions more easily assessed.

bioengineering↗
bioRxiv2017

MICCS: A Fully Programmable Multipurpose Integrated Cell Culture System

With the rise of research utilizing microphysiological systems (MPSs), the need for tools that enable the physiological mimicking of the relevant cellular environment is vital. The limited ability to reproduce crucial features of the microenvironment, such as surrounding fluid flow and dynamic changes in biochemical stimuli, severely limits the types of experiments that can be carried out. Current equipment to achieve this, such as syringe and peristaltic pumps, is expensive, large, difficult to program and has limited potential for scalability. Here, we present a new pumping platform that is open-source, low-cost, modular, scalable, fully-programmable and easy to assemble that can be incorporated into cell culture systems to better recapitulate physiological environments. By controlling two commercially available piezoelectric pumps using a Raspberry Pi Zero microcontroller, the system is capable of producing arbitrary dynamic flow profiles with reliable flow rates ranging from 1 to 3,000 {micro}L/min as specified by an easily programmable Python-based script. We validated the accuracy of the flow rates, the use of time-varying profiles, and the practicality of the system by creating repeatable dynamic concentration profiles using a 3D-printed static micromixer.

bioengineering↗
bioRxiv2017

Deep-learning based hologram classification for molecular diagnostics

Lens-free digital in-line holography (LDIH) is a promising microscopic tool that overcomes several drawbacks (e.g., limited field of view) of traditional lens-based microcopy. However, extensive computation is required to reconstruct object images from the complex diffraction patterns produced by LDIH, which limits LDIH utility for point-of-care applications, particularly in resource limited settings. Here, we describe a deep transfer learning (DTL) based approach to process LDIH images in the context of cellular analyses. Specifically, we captured holograms of cells labeled with molecular-specific microbeads and trained neural networks to classify these holograms without reconstruction. Using raw holograms as input, the trained networks were able to classify individual cells according to the number of cell-bound microbeads. The DTL-based approach including a VGG19 pretrained network showed robust performance even with noisy experimental data. Combined with the developed DTL approach, LDIH could be realized as a low-cost, portable tool for point-of-care diagnostics.

bioengineering↗
bioRxiv2017

Non-Elastic Remodeling of the 3D Extracellular Matrix by Cell-Generated Forces

The mechanical properties of the extracellular matrix (ECM) - a complex, 3D, fibrillar scaffold of cells in physiological environments - modulate cell behavior and can drive tissue morphogenesis, regeneration, and disease progression. For simplicity, it is often convenient to assume these properties to be time-invariant. In living systems, however, cells dynamically remodel the ECM and create time-dependent local environments. Here, we demonstrate that cell generated contractile forces are capable of producing substantial irreversible changes to the density and architecture of physiologically relevant ECMs - collagen I and fibrin - in a matter of minutes. We measure the 3D mechanical deformation profiles of the ECM surrounding cancer and endothelial cells during stages when force generation is active or inactive. We further correlate these measurements to both discrete fiber simulations that incorporate fiber crosslink unbinding kinetics and continuum-scale modeling. Our findings reveal that plasticity, as a mechanical law in these networks, is fundamentally related to the force-driven unbinding of fiber crosslinks. These results illustrate the dynamic nature of the mechanical environment of physiologically mimicking cell-in-gel systems.

bioengineering↗
bioRxiv2017

Depth Dependent Nanomechanical Analysis of Extracellular Matrix in Multicell Spheroids.

O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=124 SRC=\"FIGDIR/small/193516_ufig1.gif\" ALT=\"Figure 1\">\nView larger version (44K):\norg.highwire.dtl.DTLVardef@4ba6b3org.highwire.dtl.DTLVardef@ad3c2dorg.highwire.dtl.DTLVardef@149e92corg.highwire.dtl.DTLVardef@16b6e51_HPS_FORMAT_FIGEXP M_FIG C_FIG Nanomechanical investigation with Atomic Force Microscope has revealed new details regarding various nanomechanical heterogeneities for cells that are embedded in extracellular matrix in Multicellular spheroidal culture. This investigation sheds new insight into dynamic relationship of cells with their surrounding environment in tumors and 3D multicellular cultures.\n\nNanotechnology has revolutionized the field of cancer biology and has opened new avenues towards understanding nanomechanical variations in rapidly growing tumors. Over the last decade Atomic Force Microscope (AFM) has played an important role in understanding nanomechanical properties of various cancer cell lines. This study is focused on Lewis Lung Carcinoma Cell (LLC) tumors as 3D multicellular spheroid (MS). Such multicellular structures have enabled investigation of various components of tumors in-vitro. To better comprehend mechanical properties of cells and its surrounding extracellular matrix (ECM), depth dependent indentation measurements were conducted with Atomic Force Microscope (AFM). Force-vs-indentation curves were used to create stiffness profiles as function of depth. Here studies were focused on outer most layer i.e. proliferation zone of the spheroid. AFM investigations of sample a MS revealed three nanomechanical topographies, Type A- high modulus due to collagen stress fibers, Type B- high stiffness at cell membrane & ECM interface and Type C - increased modulus due to cell lying deep inside matrix at the a depth of 1.35 microns. Various nanomechanical heterogeneities revealed in this investigation can shed new light in developing correct dosage regime for various tumor dissolving drugs and designing more controlled artificial extracellular matrix systems for replicating tissue growth in-vitro.\n\nShort Statistical SummaryThis article describes nanomechanical characteristics of the cells embedded in extracellular matrix in a multicellular spheroid. The paper contains 6350 words including title page and references. Graphical Content contains 46 words. This article contains 6 Figures and zero tables.

bioengineering↗
bioRxiv2017

Evaluating Internal Model Strength and Performance of Myoelectric Prosthesis Control Strategies

Ongoing developments in myoelectric prosthesis control have provided prosthesis users with an assortment of control strategies that vary in reliability and performance. Many studies have focused on improving performance by providing feedback to the user, but have overlooked the effect of this feedback on internal model development, which is key to improving long-term performance. In this work, the strength of internal models developed for two commonly used myoelectric control strategies: raw control with raw feedback (using a regression-based approach), and filtered control with filtered feedback (using a classifier-based approach), were evaluated using two psychometric measures: trial-by-trial adaptation and just-noticeable-difference. The performance of both strategies was also evaluated using a Schmidts style target acquisition task. Results obtained from 24 able-bodied subjects showed that although filtered control with filtered feedback had better short-term performance in path efficiency (p < 0.05), raw control with raw feedback resulted in stronger internal model development (p < 0.05), which may lead to better long-term performance. Despite inherent noise in the control signals of the regression controller, these findings suggest that rich feedback associated with regression control may be used to improve human understanding of the myoelectric control system.

bioengineering↗
bioRxiv2017

Hydrogel encapsulation of living organisms for long-term microscopy

Imaging living organisms at high spatial resolution requires effective and innocuous immobilization. Long-term imaging, across development or behavioral states, places further demands on sample mounting with minimal perturbation of the organism. Here we present a simple and inexpensive method for rapid encapsulation of small animals of any developmental stage within a photocrosslinked polyethylene glycol (PEG) hydrogel, gently restricting movement within their confined spaces. Immobilized animals maintained a normal, uncompressed morphology in a hydrated environment and could be exposed to different aqueous chemicals. We focus in particular on the nematode C. elegans, an organism that is typically viewed with paralyzing reagents, nanobeads, adhesives, or microfluidic traps. The hydrogel is optically clear, non-autofluorescent, and nearly index-matched with water for use with light-sheet microscopy. We captured volumetric images of optogenetically-stimulated responses in multiple sensory neurons over 14 hours using a diSPIM light-sheet microscope, and immobilized worms were recoverable and viable after 24 hours encapsulation. We further imaged living pygmy squid hatchlings to demonstrate size scalability, characterized immobilization quality for various crosslinking parameters and identified paralytic-free conditions suitable for high-resolution single cell imaging. PEG hydrogel encapsulation enables continuous observation for hours of small living organisms, from yeast to zebrafish, and is compatible with multiple microscope mounting geometries.

bioengineering↗