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.
This article will demonstrate how to monitor glutamine dynamics in live cells using FRET. Genetically encoded sensors allow real-time monitoring of biological molecules at a subcellular resolution. Experimental design, technical details of the experimental settings, and considerations for post-experimental analyses will be discussed for genetically encoded glutamine sensors.
Published July 31, 2014. Keywords: Bioengineering, glutamine sensors, FRET, metabolites, in vivo imaging, cellular transport, genetically encoded sensors
1Institute of Pharmacology and Toxicology and Bio-Imaging Center/Rudolf Virchow Center, DFG-Research Center for Experimental Biomedicine, University of Würzburg, Germany
This protocol describes how to use total internal reflection fluorescence microscopy to visualize and track single receptors on the surface of living cells and thereby analyze receptor lateral mobility, size of receptor complexes as well as to visualize transient receptor-receptor interactions. This protocol can be extended to other membrane proteins.
Published July 25, 2014. Keywords: Bioengineering, pharmacology, microscopy, receptor, live-cell imaging, single-molecule, total internal reflection fluorescence, tracking, dimerization, protein-protein interactions
1The School of Plant Sciences, University of Arizona, 2Department of Chemical Engineering and Materials Science, DOE Great Lakes Bioenergy Research Center, Michigan State University, 3The Institute for Sustainable and Renewable Resources, The Institute for Advanced Learning and Research, 4Department of Plant, Soil and Microbial Sciences, Michigan State University
A double stranded RNA interference (dsRNAi) technique is employed to down-regulate the maize cinnamoyl coenzyme A reductase (ZmCCR1) gene to lower plant lignin content. Lignin down-regulation from the cell wall is visualized by microscopic analyses and quantified by the Klason method. Compositional changes in hemicellulose and crystalline cellulose are analyzed.
Published July 23, 2014. Keywords: Bioengineering, Zea mays, cinnamoyl-CoA reductase (CCR), dsRNAi, Klason lignin measurement, cell wall carbohydrate analysis, gas chromatography (GC)
1Joint Department of Biomedical Engineering, North Carolina State University & University of North Carolina at Chapel Hill, 2Department of Physical Medicine and Rehabilitation, University of North Carolina School of Medicine, 3Atlantic Prosthetics & Orthotics, LLC
Neural-machine interfaces (NMI) have been developed to identify the user's locomotion mode. These NMIs are potentially useful for neural control of powered artificial legs, but have not been fully demonstrated. This paper presented (1) our designed engineering platform for easy implementation and development of neural control for powered lower limb prostheses and (2) an experimental setup and protocol in a laboratory environment to evaluate neurally-controlled artificial legs on patients with lower limb amputations safely and efficiently.
Published July 22, 2014. Keywords: Biomedical Engineering, neural control, powered transfemoral prosthesis, electromyography (EMG), neural-machine interface, experimental setup and protocol
1Department of Immunology, National Jewish Health, 2Department of Pharmacology, School of Medicine, University of Colorado Denver
The reliability of results in metabolomics experiments depends on the effectiveness and reproducibility of the sample preparation. Described is a rigorous and in-depth method that enables extraction of metabolites from biological fluids with the option of subsequently analyzing up to thousands of compounds, or just the compound classes of interest.
Published July 11, 2014. Keywords: Bioengineering, plasma, chemistry techniques, analytical, solid phase extraction, mass spectrometry, metabolomics, fluids and secretions, profiling, small molecules, lipids, liquid chromatography, liquid-liquid extraction, cerebrospinal fluid, bronchoalveolar lavage fluid
1Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California
In this article, we describe a protocol for fabricating an amelogenin-chitosan hydrogel for superficial enamel reconstruction. Organized in situ growth of apatite crystals in the hydrogel formed a dense enamel-restoration interface, which will improve the effectiveness and durability of restorations.
Published July 10, 2014. Keywords: Bioengineering, Enamel, Amelogenin, Chitosan hydrogel, Apatite, Biomimetic, Erosion, Superficial enamel reconstruction, Dense interface
1Geotechnical and Structures Laboratory, U.S. Army Engineer Research and Development Center, 2Department of Mechanical Engineering, University of Alabama, 3Environmental Laboratory, U.S. Army Engineer Research and Development Center
This paper presents the methods used for probing spatially correlated chemical, structural, and mechanical properties of the multilayered scale of Atractosteus spatula (A. spatula) using nanoindentation, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and X-ray computed tomography (X-ray CT). The experimental results have been used to investigate the design principles of protective biological materials.
Published July 10, 2014. Keywords: Bioengineering, Atractosteus spatula, structure-property relation, nanoindentation, scan electron microscopy, X-ray computed tomography, Fourier transform infrared (FTIR) spectroscopy
1United States Army-Natick Soldier RD&E Center, Warfighter Directorate, 2Department of Molecular Biology and Biophysics, University of Connecticut Health Center, 3Lawrence Livermore National Laboratory, 4Children's Hospital Oakland Research Institute
The Portable Chemical Sterilizer (PCS) is a revolutionary, energy-independent, almost waterless sterilization technology for Army medical units. The PCS generates chlorine dioxide from dry reagents mixed with water on-site, at-will, and at point-of-use (PoU) in a plastic suitcase. The Disinfectant-sprayer for Foods and ENvironmentally-friendly Sanitation (D-FENS) and the Disinfectant for ENvironmentally-friendly Decontamination, All-purpose (D-FEND ALL) produce aqueous chlorine dioxide in a collapsible spray bottle and other potential embodiments. These versatile decontamination technologies kill microbes in myriad diverse Dual-use applications for military and civilian consumers.
Published June 29, 2014. Keywords: Bioengineering, chlorine dioxide, novel technologies, D-FENS, PCS, and D-FEND ALL, sterilization, decontamination, fresh produce safety
1Department of Bioengineering & Therapeutic Sciences, University of California, San Francisco, 2Department of Obstetrics, Gynecology & Reproductive Sciences, University of California, San Francisco, 3Keck School of Medicine, University of Southern California
We have devised a method for low-cost and rapid prototyping of liquid elastomer rubber injection molded devices by using fused deposition modeling 3D printers for mold design and a modified desiccator as a liquid injection system.
Published June 27, 2014. Keywords: Bioengineering, liquid injection molding, reaction injection molding, molds, 3D printing, fused deposition modeling, rapid prototyping, medical devices, low cost, low volume, rapid turnaround time.
1Department of Biomedical Engineering, Florida International University
Synthesis and fabrication of electrospun long fibers spanning a larger deposit area via a newly designed collector from a novel biodegradable polymer named poly(glycerol-dodecanoate) (PGD) was reported. The fibers were able to support the growth of cells derived from mouse pluripotent stem cells.
Published June 18, 2014. Keywords: Bioengineering, tissue engineering, electrospinning, fiber scaffolds, Poly(glycerol-dodecanedioate) (PGD), gelatin, Mouse embryonic stem cells