Drexel University

Manipulating fluids and suspended particles in the micro- and nano-scale is becoming more of a reality as enabling technologies, like AC electrokinetics, continue to develop. Here, we discuss the physics behind AC electrokinetics, how to fabricate these devices and how to interpret the experimental observations.

The Ugi reaction has proved to be a convenient way to quickly create diverse libraries of compounds. It involves the reaction of an amine, an aldehyde, a carboxylic acid and an isonitrile typically in methanol at room temperature. In this video, we utilize a 48-slot Mettler-Toledo MiniBlock equipped with filtration tubes and a Mettler-Toledo MiniMapper automated liquid handler was used to deliver the reagents and solvent. The parameters of interest were the concentration, the solvent composition and the excess of some of the reagents.

MazeSuite is a complete toolset to prepare, present and analyze navigational and spatial experiments. Functional near-infrared spectroscopy (fNIR) is an optical brain imaging technique that enables noninvasive and portable monitoring of cerebral blood oxygenation changes. This paper summarizes collective use of MazeSuite and fNIR within a cognitive processing learning paradigm.

Untargeted metabolomics provides a hypothesis generating snapshot of a metabolic profile. This protocol will demonstrate the extraction and analysis of metabolites from cells, serum, or tissue. A range of metabolites are surveyed using liquid-liquid phase extraction, microflow ultraperformance liquid chromatography/high-resolution mass spectrometry (UPLC-HRMS) coupled to differential analysis software.

This article describes a detailed protocol to produce a forebrain stab injury in adult mice. The stab injury induces severe reactive gliosis and glial scar formation which can be subsequently examined by standard immunohistochemistry methods.

A novel reactor design, coined a high density bioreactor (HDBR), is presented for the cultivation and study of high density microbial communities. Here, the HDBR is successfully applied in a photobioreactor (PBR) configuration for the study of nitrogen metabolism by a mixed high density algal community.

An injectable tissue engineering scaffold composed of poly(N-isopropylacrylamide)-graft-chondroitin sulfate (PNIPAAm-g-CS)-containing alginate microparticles was prepared. The adhesive strength, swelling properties and in vitro biocompatibility are analyzed in this study. The characterization techniques developed here may be applicable to other thermogelling systems.

Here we show isolated human platelets can be used as an accessible ex vivo model to study metabolic adaptations in response to the complex I inhibitor rotenone. This approach employs isotopic tracing and relative quantification by liquid chromatography-mass spectrometry and can be applied to a variety of study designs.

An experimental methodology is presented to compare the performance of small (100 L) and large (1,000 L) scale reactors designed for algae remediation of landfill wastewater. System characteristics, including surface area to volume ratio, retention time, biomass density, and wastewater feed concentrations, can be adjusted based on application.

This manuscript details the fabrication of micro-tissue engineered neural networks: three-dimensional micron-sized constructs comprised of long aligned axonal tracts spanning aggregated neuronal population(s) encased in a tubular hydrogel. These living scaffolds can serve as functional relays to reconstruct or modulate neural circuitry or as biofidelic test-beds mimicking gray-white matter neuroanatomy.

We showcase the development of self-assembled, three-dimensional bundles of longitudinally aligned astrocytic somata and processes within a novel biomaterial encasement. These engineered "living scaffolds", exhibiting micron-scale diameter yet extending centimeters in length, may serve as test-beds to study neurodevelopmental mechanisms or facilitate neuroregeneration by directing neuronal migration and/or axonal pathfinding.

This protocol describes a method for calculating Heart Rate Variability (HRV) from electrocardiogram (ECG) waveforms. Waveforms from continuous heart rate (HR) recordings during active video game (AVG) sessions were used to measure the aerobic performance of youth with cerebral palsy (CP).

Presented here are methods to perform in vivo biomechanical testing on brachial plexus in a neonatal piglet model.

We describe here a method for fabricating Ti₃C₂ MXene microelectrode arrays and utilizing them for in vivo neural recording.

We describe a method of inducing hairy roots by Agrobacterium rhizogenes-mediated transformation in Tartary buckwheat (Fagopyrum tataricum). This can be used to investigate gene functions and production of secondary metabolites in Tartary buckwheat, be adopted for any genetic transformation, or used for other medicinal plants after improvement.

Rip currents are among the deadliest meteorological hazards in the United States. In order to demonstrate the proper actions to take when caught in a rip current in a memorable and engaging way, a virtual reality video game is developed.

The goal of this protocol is to directly bioprint breast epithelial cells as multicellular spheroids onto pre-formed endothelial networks to rapidly create 3D breast-endothelial co-culture models which can be used for drug screening studies.

The goal was to design, build, and pilot a novel virtual reality task to detect and characterize unilateral spatial neglect, a syndrome affecting 23-46% of acute stroke survivors, expanding the role of virtual reality in the study and management of neurologic disease.

A protocol for noninvasively estimating ambient pressures utilizing subharmonic ultrasound imaging of infused contrast microbubbles (following appropriate calibration) is described with examples from human patients with chronic liver disease.

Presented here is a mild 3D printing technique driven by alternating viscous-inertial forces to enable the construction of hydrogel microcarriers. Homemade nozzles offer flexibility, allowing easy replacement for different materials and diameters. Cell binding microcarriers with a diameter of 50-500 µm can be obtained and collected for further culturing.

Oxygen consumption rate (OCR) is a common proxy for mitochondrial function and can be used to study different disease models. We developed a new method using a Seahorse XF analyzer to directly measure the OCR in acute striatal slices from adult mice that is more physiologically relevant than other methods.

The present protocol determines the tensile stress-relaxation and failure properties of porcine tracheae. Results from such methods can help improve the understanding of the viscoelastic and failure thresholds of the trachea and help advance the capabilities of computational models of the pulmonary system.

This protocol implements a stereo-imaging camera system calibrated using direct linear transformation to capture three-dimensional in-situ displacements of stretched peripheral nerves. By capturing these displacements, strain induced at varying degrees of stretch can be determined informing the stretch injury thresholds that can advance the science of stretch-dependent nerve repair.