JoVE Bioengineering merges both physical and life sciences to understand and predict biological processes. Applying physical science tools to life science questions allow for the discovery of better technologies to measure, diagnose, and clinically treat disease.
1Biomedical Engineering, Laboratory for Fluorescence Dynamics, University of California, Irvine
In this video protocol we track - at high speed and in three dimensions - fluorescently labeled lysosomes within living cells, using the orbital tracking method in a modified two-photon microscope.
Published October 1, 2014. Keywords: Bioengineering, fluorescence, single particle tracking, laser scanning microscope, two-photon, vesicle transport, live-cell imaging, optics
1School of Animal and Comparative Biomedical Sciences, University of Arizona, 2Department of Entomology, University of Arizona
The goal of this presentation is to demonstrate in vivo and in vitro techniques for the rearing of entomopathogenic nematodes. In vivo methods consider the rearing of these nematodes with an insect host, whereas the in vitro methods utilize rich agar media.
Published September 22, 2014. Keywords: Bioengineering, entomology, nematology, microbiology, entomopathogenic, nematodes, bacteria, rearing, in vivo, in vitro
1Cardiology, Department of Medicine, University of Fribourg
Implantation of a biograft to treat myocardial infarction induced by LAD ligation in a rodent model has conventionally required two open-heart surgeries. In order to reduce mortality and provide optimal conditions for fixation of solid and gelatinous biomatrices associated with cells, minimally invasive procedures have been developed.
Published September 22, 2014. Keywords: Bioengineering, myocardial infarction (MI), fibrin sealant, thoracotomy, Left Anterior Descending Artery (LAD) ligation, cardiac cell therapy, cardiac microsurgery
1Department of Neural and Behavioral Sciences, Penn State University College of Medicine
The in vivo measurement of smooth muscle contractions along the gastrointestinal tract of laboratory animals remains a powerful, though underutilized, technique. Flexible, dual element strain gages are not commercially available and require fabrication. This protocol describes the construction of reliable, inexpensive strain gages for acute or chronic implantation in rodents.
Published September 18, 2014. Keywords: Bioengineering, gastrointestinal tract, gastric contractions, motility, in vivo recording, physiology, neuroscience, strain gage
1Structure et Propriétés d'Architectures Moléculaires, Institut Nanosciences et Cryogénie, CEA-Grenoble, 2Institut de Chimie Moléculaire et des Matériaux d'Orsay, Université Paris-Sud, 3Institut de Biologie Structurale
A novel approach is described for construction of electronic tongue (eT), which greatly simplifies the design and production of sensing materials, and allows the eT to generate continuous evolution profiles and landscapes for samples in liquid. The obtained eT is efficient for common protein analysis such as discrimination.
Published September 16, 2014. Keywords: Bioengineering, electronic tongue, combinatorial cross-reactive receptor, surface plasmon resonance imaging, pattern recognition, continuous evolution profiles, continuous evolution landscapes, protein analysis
1Center for Membrane Biology, Department of Biochemistry and Molecular Biology, University of Texas Health Science Center at Houston
We describe here an improved Luminescence Resonance Energy Transfer (LRET) method where we introduce a protease cleavage site between the donor and acceptor fluorophore sites. This modification allows us to obtain specific LRET signals arising from membrane proteins of interest, allowing for the study of membrane proteins without protein purification.
Published September 16, 2014. Keywords: Bioengineering, LRET, FRET, Luminescence Resonance Energy Transfer, Fluorescence Resonance Energy Transfer, glutamate receptors, acid sensing ion channel, protein conformation, protein dynamics, fluorescence, protein-protein interactions
1Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign
Traditional techniques for fabricating polyacrylamide (PA) gels containing fluorescent probes involve sandwiching a gel between an adherent surface and a glass slide. Here, we show that coating this slide with poly-D-lysine (PDL) and fluorescent probes localizes the probes to within 1.6 µm from the gel surface.
Published September 16, 2014. Keywords: Bioengineering, cell mechanics, polyacrylamide (PA) gel, traction force microscopy, fluorescent beads, poly-D-lysine (PDL), cell culture surface
1Department of Materials Science and Engineering, University of Sheffield, 2Department of Chemistry, University of Sheffield, 3L. V. Prasad Eye Institute
We report a technique for the fabrication of micropockets within electrospun membranes in which to study cell behavior. Specifically, we describe a combination of microstereolithography and electrospinning for the production of PLGA (Poly(lactide-co-glycolide)) corneal biomaterial devices equipped with microfeatures.
Published September 12, 2014. Keywords: Bioengineering, electrospinning, microstereolithography, stem cell niche, storage, limbal explants
1MEMS Sensors and Actuators Laboratory (MSAL), Department of Electrical and Computer Engineering, Institute for Systems Research, University of Maryland, 2Institute for Bioscience and Biotechnology Research, Fischell Department of Bioengineering, University of Maryland
We present a microfluidic-based electrochemical biochip for DNA hybridization detection. Following ssDNA probe functionalization, the specificity, sensitivity, and detection limit are studied with complementary and non-complementary ssDNA targets. Results illustrate the influence of the DNA hybridization events on the electrochemical system, with a detection limit of 3.8 nM.
Published September 10, 2014. Keywords: Bioengineering, electrochemical impedance spectroscopy, DNA hybridization, biosensor, biochip, microfluidics, label-free detection, restricted diffusion, microfabrication
1Department of Food Science, Pennsylvania State University
Electrospinning is a fascinating technique used to fabricate micro- to nano-scale fibers from a wide variety of materials. Molecular entanglement of the constituent polymers in the spinning dope is essential for successful electrospinning. We present a protocol for utilizing rheology to evaluate the electrospinnability of two biopolymers, starch and pullulan.
Published September 3, 2014. Keywords: Bioengineering, electrospinning, rheology, molecular entanglement, fiber, nanofiber, biopolymer, polysaccharides, starch, pullulan