Boston University View Institution's Website 41 articles published in JoVE Bioengineering A Passive Ankle Dorsiflexion Testing System for an In Vivo Model of Overuse-induced Tendinopathy Pooja H. Chainani1,2, Patrick M. Williamson1,2, Diana Yeritsyan1, Kaveh Momenzadeh1, Nadim Kheir1, Joseph P. DeAngelis1,3, Arun J. Ramappa1,3, Ara Nazarian1,2,3,4 1Musculoskeletal Translational Innovation Initiative, Carl J. Shapiro Department of Orthopaedic Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, 2Mechanical Engineering Department, Boston University, 3Carl J. Shapiro Department of Orthopaedic Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, 4Department of Orthopaedic Surgery, Yerevan State Medical University This protocol presents a testing system used to induce quantifiable and controlled fatigue injuries in a rat Achilles tendon for an in-vivo model of overuse-induced tendinopathy. The procedure consists of securing the rat's ankle to a joint actuator that performs passive ankle dorsiflexion with a custom-written MATLAB script. Cancer Research Venous Thrombosis Assay in a Mouse Model of Cancer Saran Lotfollahzadeh1, Xiaosheng Yang1, David Jasen Wu Wong1, Jingyan Han2, Francesca Seta2, Suvranu Ganguli3, Asha Jose1, Katya Ravid4,5, Vipul C. Chitalia1,6,7,8 1Renal Section, Department of Medicine, Chobanian and Avedisian School of Medicine, Boston University, 2Vascular Biology Section, Department of Medicine, Chobanian and Avedisian School of Medicine, Boston University, 3Division of Interventional Radiology, Department of Radiology, Chobanian and Avedisian School of Medicine, Boston University, 4Department of Medicine, Whitaker Cardiovascular Institute, Chobanian and Avedisian School of Medicine, Boston University, 5Department of Biochemistry and Cell Biology, Chobanian and Avedisian School of Medicine, Boston University, 6Veterans Affairs Boston Healthcare System, 7Institute of Medical Engineering and Sciences, Massachusetts Institute of Technology, 8Center of Cross-Organ Vascular Pathology, Department of Medicine, Chobanian and Avedisian School of Medicine, Boston University This article aims to present an optimized method for assessing venous thrombosis in a mouse cancer model, using vascular clips to achieve venous ligation. Optimization minimizes variability in thrombosis-related measurements and enhances relevance to human cancer-associated venous thrombosis. Biochemistry Live-Cell Imaging of Intact Ex Vivo Globes Using a Novel 3D Printed Holder Kristen L. Segars*1, Nicholas A. Azzari*2, Stephanie Gomez2, Celeste B. Rich3, Vickery Trinkaus-Randall2,3 1Department of Pharmacology, School of Medicine, Boston University, 2Department of Biochemistry, School of Medicine, Boston University, 3Department of Ophthalmology, School of Medicine, Boston University The present work describes a novel experimental protocol that utilizes a 3D printed holder to enable high-resolution live cell imaging of enucleated globes. Through this protocol, the cellular calcium signaling activity in wounded corneal epithelium from ex vivo globes can be observed in real time. Bioengineering Design to Implementation Study for Development and Patient Validation of Paper-Based Toehold Switch Diagnostics Katariina Jaenes*1, Severino Jefferson Ribeiro da Silva*1,2, Justin R. J. Vigar*1, Kaiyue Wu3,4, Masoud Norouzi1, Pouriya Bayat1, Margot Karlikow1, Seray Cicek1, Yuxiu Guo1, Alexander A. Green3,4, Lindomar Pena2, Keith Pardee1,5 1Leslie Dan Faculty of Pharmacy, University of Toronto, 2Laboratory of Virology and Experimental Therapy (LAVITE), Department of Virology, Aggeu Magalhães Institute (IAM), Oswaldo Cruz Foundation (Fiocruz), 3Department of Biomedical Engineering, Boston University, 4Molecular Biology, Cell Biology & Biochemistry Program, Graduate School of Arts and Sciences, Boston University, 5Department of Mechanical and Industrial Engineering, University of Toronto Access to decentralized, low-cost, and high-capacity diagnostics that can be deployed into the community for decentralized testing is critical for combating global health crises. This manuscript describes how to build paper-based diagnostics for viral RNA sequences that can be detected with a portable optical reader. Bioengineering Pattern Generation for Micropattern Traction Microscopy Katie A. Bunde1, Dimitrije Stamenović1, Michael L. Smith1 1Department of Biomedical Engineering, Boston University We describe improvements to a standard method for measuring cellular traction forces, based on microcontact printing with a single subtractive patterning step of dot arrays of extracellular matrix proteins on soft hydrogels. This method allows for simpler and more consistent fabrication of island patterns, essential for controlling cell cluster shape. Biology Rapid Antimicrobial Susceptibility Testing by Stimulated Raman Scattering Imaging of Deuterium Incorporation in a Single Bacterium Meng Zhang1,2, Mohamed N. Seleem3, Ji-Xin Cheng1,2,4,5 1Department of Electrical and Computer Engineering, Boston University, 2Boston University Photonics Center, Boston University, 3Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Polytechnic Institute and State University, 4Department of Biomedical Engineering, Boston University, 5Department of Chemistry, Boston University This protocol presents rapid antimicrobial susceptibility testing (AST) assay within 2.5 h by single-cell-stimulated Raman scattering imaging of D2O metabolism. This method applies to bacteria in the urine or whole blood environment, which is transformative for rapid single-cell phenotypic AST in the clinic. Neuroscience The Impact of Motor Task Conditions on Goal-Directed Arm Reaching Kinematics and Trunk Compensation in Chronic Stroke Survivors Jaimie Girnis1,2, Tarek Agag1, Tobias Nobiling1,3, Vanessa Sweet1,4, Bokkyu Kim1 1Department of Physical Therapy Education, SUNY Upstate Medical University, 2College of Health and Rehabilitation Sciences: Sargent College Center for Neurorehabilitation, Boston University, 3Department of Physical Medicine and Rehabilitation, University of Rochester Medical Center, 4Rehabilitation Today This protocol is intended to investigate the impact of task conditions on movement strategies in chronic stroke survivors. Further, this protocol can be used to examine if a restriction in elbow extension induced by neuromuscular electrical stimulation causes trunk compensation during goal-directed arm reaches in non-disabled adults. Biology A Pipeline using Bilateral In Utero Electroporation to Interrogate Genetic Influences on Rodent Behavior Ashley L. Comer1,2,3,4, Balaji Sriram5, William W. Yen2, Alberto Cruz-Martín1,2,3,4,6 1The Graduate Program for Neuroscience, Boston University, 2Department of Biology, Boston University, 3Neurophotonics Center, Boston University, 4Center for Systems Neuroscience, Boston University, 5Research and Early Development, Biogen, 6Department Pharmacology and Experimental Therapeutics, Boston University The role of recently discovered disease-associated genes in the pathogenesis of neuropsychiatric disorders remains obscure. A modified bilateral in utero electroporation technique allows for the gene transfer in large populations of neurons and examination of the causative effects of gene expression changes on social behavior. Chemistry NMR-Based Activity Assays for Determining Compound Inhibition, IC50 Values, Artifactual Activity, and Whole-Cell Activity of Nucleoside Ribohydrolases Brian J. Stockman1, Abinash Kaur1, Julia K. Persaud1, Maham Mahmood1, Samantha F. Thuilot1, Melissa B. Emilcar1, Madison Canestrari1, Juliana A. Gonzalez1, Shannon Auletta1, Vital Sapojnikov1, Wagma Caravan1,2, Samantha N. Muellers1,3 1Department of Chemistry, Adelphi University, 2Department of Chemistry, Washington University in St. Louis, 3Department of Chemistry, Boston University NMR-based activity assays have been developed to identify and characterize inhibitors of two nucleoside ribohydrolase enzymes. Protocols are provided for initial compound assays at 500 μM and 250 μM, dose-response assays for determining IC50 values, detergent counter screen assays, jump-dilution counter screen assays, and assays in E. coli whole cells. Genetics Designing Automated, High-throughput, Continuous Cell Growth Experiments Using eVOLVER Zachary J. Heins1,2, Christopher P. Mancuso1,2, Szilvia Kiriakov1,3, Brandon G. Wong1,2, Caleb J. Bashor4, Ahmad S. Khalil1,2,5 1Biological Design Center, Boston University, 2Department of Biomedical Engineering, Boston University, 3Program in Molecular Biology, Cell Biology and Biochemistry, Boston University, 4Department of Bioengineering, Rice University, 5Wyss Institute for Biologically Inspired Engineering, Harvard University The eVOLVER framework enables high-throughput continuous microbial culture with high resolution and dynamic control over experimental parameters. This protocol demonstrates how to apply the system to conduct a complex fitness experiment, guiding users on programming automated control over many individual cultures, measuring, collecting, and interacting with experimental data in real-time. Genetics ATAC-seq Assay with Low Mitochondrial DNA Contamination from Primary Human CD4+ T Lymphocytes Hannah D. Rickner1, Sheng-Yong Niu1,2, Christine S. Cheng1,3 1Department of Biology, Boston University, 2Department of Computer Science and Engineering, University of California San Diego, 3Bioinformatics Program, Boston University Here, we present a protocol to perform an assay for transposase-accessible chromatin sequencing (ATAC-seq) on activated CD4+ human lymphocytes. The protocol has been modified to minimize contaminating mitochondrial DNA reads from 50% to 3% through the introduction of a new lysis buffer. Genetics Enhanced Yeast One-hybrid Screens To Identify Transcription Factor Binding To Human DNA Sequences Shaleen Shrestha*1, Xing Liu*1, Clarissa Stephanie Santoso*1, Juan Ignacio Fuxman Bass1,2 1Department of Biology, Boston University, 2Bioinformatics Program, Boston University Here, we present an enhanced yeast one-hybrid screening protocol to identify the transcription factors (TFs) that can bind to a human DNA region of interest. This method uses a high-throughput screening pipeline that can interrogate the binding of >1,000 TFs in a single experiment. Genetics Chromatin Immunoprecipitation of Murine Brown Adipose Tissue Maria Dafne Cardamone1, Joseph Orofino1, Adam Labadorf2, Valentina Perissi1 1Biochemistry Department, Boston University School of Medicine, 2Bioinformatic Hub, Boston University Here we describe a protocol for efficient chromatin immunoprecipitation (ChIP) followed by high-throughput DNA sequencing (ChIP-seq) of brown adipose tissue (BAT) isolated from a mouse. This protocol is suitable for both mapping histone modifications and investigating genome-wide localization of non-histone proteins of interest in vivo. Bioengineering Rat Model of Adhesive Capsulitis of the Shoulder Stephen M. Okajima*1, M. Belen Cubria*1, Sharri J. Mortensen1, Juan C. Villa-Camacho1, Philip Hanna1, Aron Lechtig1, Miguel Perez-Viloria1, Patrick Williamson1, Mark W. Grinstaff*3, Edward K. Rodriguez*2, Ara Nazarian*1,4 1Center for Advanced Orthopaedic Studies, Beth Israel Deaconess Medical Center and Harvard Medical School, 2Carl J. Shapiro Department of Orthopaedic Surgery, Beth Israel Deaconess Medical Center and Harvard Medical School, 3Departments of Biomedical Engineering, Chemistry, and Medicine, Boston University, 4Department of Orthopaedic Surgery, Yerevan State Medical University This protocol presents an in vivo rat model of adhesive capsulitis. The model includes an internal fixation of the glenohumeral joint with extra-articular suture fixation for an extended time, resulting in a decreased rotational range of motion (ROM) and increased joint stiffness. Bioengineering Multimodal Volumetric Retinal Imaging by Oblique Scanning Laser Ophthalmoscopy (oSLO) and Optical Coherence Tomography (OCT) Weiye Song*1, Libo Zhou*1, Ji Yi1,2 1Department of Medicine, Boston University School of Medicine, 2Department of Biomedical Engineering, Boston University Here, we present a protocol to get a large field of view (FOV) three-dimensional (3D) fluorescence and OCT retinal image by using a novel imaging multimodal platform. We will introduce the system setup, the method of alignment, and the operational protocols. In vivo imaging will be demonstrated, and representative results will be provided. Neuroscience Neurovascular Network Explorer 2.0: A Simple Tool for Exploring and Sharing a Database of Optogenetically-evoked Vasomotion in Mouse Cortex In Vivo Hana Uhlirova1,2, Peifang Tian3,4, Kıvılcım Kılıç3,5, Martin Thunemann1, Vishnu B. Sridhar6, Radim Chmelik2,7, Hauke Bartsch1, Anders M. Dale1,3, Anna Devor1,3,8, Payam A. Saisan3 1Department of Radiology, University of California, San Diego, 2Central European Institute of Technology, Brno University of Technology, 3Department of Neurosciences, University of California, San Diego, 4Department of Physics, John Carroll University, 5Department of Biomedical Engineering, Boston University, 6Bioengineering Undergraduate Program, University of California, San Diego, 7Institute of Physical Engineering, Faculty of Mechanical Engineering, Brno University of Technology, 8Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School A graphical user interface for exploring and sharing a database of optogenetically-induced vascular responses in mouse somatosensory cortex in vivo measured by 2-photon microscopy is presented. It allows browsing the data, criteria-based selection, averaging, localization of measurements within a 3D volume of vasculature and exporting the data. Bioengineering Preparation, Purification, and Use of Fatty Acid-containing Liposomes Lin Jin*1,2, Aaron E. Engelhart*1,3, Katarzyna P. Adamala1,3, Jack W. Szostak1 1Howard Hughes Medical Institute and Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 2Department of Biomedical Engineering, Boston University, 3Department of Genetics, Cell Biology, and Development, University of Minnesota Liposomes containing single-chain amphiphiles, particularly fatty acids, exhibit distinct properties compared to those containing diacylphospholipids due to the unique chemical properties of single chain amphiphiles. Here we describe techniques for the preparation, purification, and use of liposomes comprised in part or whole of these amphiphiles. Bioengineering Automated Robotic Liquid Handling Assembly of Modular DNA Devices Luis Ortiz1,2, Marilene Pavan2, Lloyd McCarthy3, Joshua Timmons3, Douglas M. Densmore4 1Graduate Program in Molecular Biology, Cell Biology, and Biochemistry, Boston University, 2Biological Design Center, Boston University, 3Lattice Automation, 4Department of Electrical and Computer Engineering, Biological Design Center, Boston University Here, an automated workflow to perform modular DNA "device" assembly using a modular cloning DNA assembly method on liquid-handling robots is presented. The protocol uses an intuitive software tool for generating liquid handler picklists for combinatorial DNA device library generation, which we demonstrate using two liquid handling platforms. Biology DiI Perfusion as a Method for Vascular Visualization in Ambystoma mexicanum Anna J. Saltman*1,2, May Barakat*1, Donald M. Bryant1, Anastasia Brodovskaya1, Jessica L. Whited1 1 Using a lipophilic 1,1'-Dioctadecy-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI) staining technique, Ambystoma mexicanum can undergo vascular perfusion to allow for easy visualization of the vasculature. Behavior A Within-subjects Experimental Protocol to Assess the Effects of Social Input on Infant EEG Ashley M. St. John1, Katie Kao1, Meia Chita-Tegmark1, Jacqueline Liederman1, Philip G. Grieve2, Amanda R. Tarullo1 1Department of Psychological and Brain Sciences, Boston University, 2Department of Pediatrics, Columbia University Medical Center This novel protocol is designed to assess the neural bases of social interaction in infants. The paradigm is designed to tease apart how various social inputs such as language, joint attention, and face-to-face interaction relate to infant neural activation. Infant EEG power is recorded during both social and nonsocial conditions. Engineering Synthesis of Ionic Liquid Based Electrolytes, Assembly of Li-ion Batteries, and Measurements of Performance at High Temperature Xinrong Lin1, Jennifer Chapman Varela1, Mark W. Grinstaff1,2,3 1Department of Chemistry, Boston University, 2Department of Biomedical Engineering, Boston University, 3Department of Medicine, Boston University Here, we describe protocols to prepare phosphonium-based ionic liquid and lithium bis(trifluoromethane)sulfonimide salt electrolytes, and assemble a non-flammable and high temperature functioning lithium-ion coin cell battery. Bioengineering A Microfluidic Platform for Precision Small-volume Sample Processing and Its Use to Size Separate Biological Particles with an Acoustic Microdevice Erika J. Fong1,2, Chao Huang1, Julie Hamilton1, William J. Benett1, Mihail Bora1, Alison Burklund1, Thomas R. Metz1, Maxim Shusteff1 1Materials Engineering Division, Lawrence Livermore National Laboratory, 2Department of Biomedical Engineering, Boston University This protocol describes a system architecture for performing automated small volume (0.15–1.5 ml) particle separations using a microfluidic device, and discusses methods to optimize acoustofluidic device performance and operation. Bioengineering Fabricating Superhydrophobic Polymeric Materials for Biomedical Applications Jonah Kaplan1, Mark Grinstaff2 1Department of Biomedical Engineering, Boston University, 2Departments of Biomedical Engineering, Chemistry, and Medicine, Boston University Two- and three-dimensional superhydrophobic polymeric materials are prepared by electrospinning or electrospraying biodegradable polymers blended with a lower surface energy polymer of similar composition. Medicine Do's and Don'ts in the Preparation of Muscle Cryosections for Histological Analysis Ajay Kumar*1, Anthony Accorsi*1, Younghwa Rhee1, Mahasweta Girgenrath1 1Sargent College, Boston University Here we demonstrate the most efficient methods for freezing, embedding, cryosectioning, and staining of muscle biopsies to avoid freezing artifacts. Medicine Heterotopic Mucosal Engrafting Procedure for Direct Drug Delivery to the Brain in Mice Richie E. Kohman1, Xue Han1, Benjamin S. Bleier2 1Department of Biomedical Engineering, Boston University, 2Department of Otology and Laryngology, Massachusetts Eye and Ear Infirmary, Harvard Medical School A mouse model of human endoscopic skull base reconstruction has been developed that creates a semipermeable interface between the brain and nose using nasal mucosal grafts. This method allows researchers to study delivery to the central nervous system of high molecular weight therapeutics which are otherwise excluded by the blood-brain barrier when administered systemically. Environment A Noninvasive Method For In situ Determination of Mating Success in Female American Lobsters (Homarus americanus) Jason S Goldstein1, Tracy L Pugh1,2, Elizabeth A Dubofsky1, Kari L Lavalli3, Michael Clancy4, Winsor H Watson III1 1Department of Biological Sciences, University of New Hampshire, 2Massachusetts Division of Marine Fisheries, 3Division of Natural Sciences & Mathematics, College of General Studies, Boston University, 4Rhode Island Nursing Institute, Middle College Fishery-induced changes to exploited crustacean fisheries, such as the American lobster fishery, could potentially influence their reproductive dynamics, leading to a reduction in mating success. This study's goal was to develop a noninvasive method for ascertaining the mating success of female lobsters that may be physiologically or functionally mature. Bioengineering Stress-induced Antibiotic Susceptibility Testing on a Chip Maxim Kalashnikov1, Jennifer Campbell1, Jean C. Lee2, Andre Sharon1,3, Alexis F. Sauer-Budge1,4 1Fraunhofer USA Center for Manufacturing Innovation, 2Division of Infectious Diseases, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, 3Department of Mechanical Engineering, Boston University, 4Department of Biomedical Engineering, Boston University We have developed a microfluidic platform for rapid antibiotic susceptibility testing. Fluid is passed at high speeds over bacteria immobilized on the bottom of a microfluidic channel. In the presence of stress and antibiotic, susceptible strains of bacteria die rapidly. However, resistant bacteria can survive these stressful conditions. Neuroscience In vivo Neuronal Calcium Imaging in C. elegans Samuel H. Chung*1,2, Lin Sun*1,2, Christopher V. Gabel1,2 1Department of Physiology and Biophysics, Boston University School of Medicine, 2Boston University Photonics Center With its small transparent body, well-documented neuroanatomy and a host of amenable genetic techniques and reagents, C. elegans makes an ideal model organism for in vivo neuronal imaging using relatively simple, low-cost techniques. Here we describe single neuron imaging within intact adult animals using genetically encoded fluorescent calcium indicators. Bioengineering Microfluidic Chip Fabrication and Method to Detect Influenza Qingqing Cao1, Andy Fan2, Catherine Klapperich1,2 1Department of Mechanical Engineering, Boston University, 2Department of Biomedical Engineering, Boston University An integrated microfluidic thermoplastic chip has been developed for use as a molecular diagnostic. The chip performs nucleic acid extraction, reverse transcriptase, and PCR. Methods for fabricating and running the chip are described. Biology Generation of Human Induced Pluripotent Stem Cells from Peripheral Blood Using the STEMCCA Lentiviral Vector Andreia Gianotti Sommer1, Sarah S. Rozelle1, Spencer Sullivan2, Jason A. Mills3, Seon-Mi Park1, Brenden W. Smith1, Amulya M. Iyer1, Deborah L. French3, Darrell N. Kotton1, Paul Gadue3, George J. Murphy1, Gustavo Mostoslavsky1 1Center for Regenerative Medicine (CReM), Boston University School of Medicine, 2Department of Hematology, Children's Hospital of Philadelphia, 3Center for Cellular and Molecular Therapeutics, Children's Hospital of Philadelphia Here we show a simple and effective protocol for the generation of human iPSCs from 3-4 ml of peripheral blood using a single lentiviral reprogramming vector. Reprogramming of readily available blood cells promises to accelerate the utilization of iPSC technology by making it accessible to a broader research community. Engineering Synthesis of Phase-shift Nanoemulsions with Narrow Size Distributions for Acoustic Droplet Vaporization and Bubble-enhanced Ultrasound-mediated Ablation Jonathan A. Kopechek1, Peng Zhang1, Mark T. Burgess1, Tyrone M. Porter1 1Department of Mechanical Engineering, Boston University Phase-shift nanoemulsions (PSNE) can be vaporized using high intensity focused ultrasound to enhance localized heating and improve thermal ablation in tumors. In this report, the preparation of stable PSNE with a narrow size distribution is described. Furthermore, the impact of vaporized PSNE on ultrasound-mediated ablation is demonstrated in tissue-mimicking phantoms. Biology A Faster, High Resolution, mtPA-GFP-based Mitochondrial Fusion Assay Acquiring Kinetic Data of Multiple Cells in Parallel Using Confocal Microscopy Alenka Lovy1, Anthony J.A. Molina2, Fernanda M. Cerqueira3, Kyle Trudeau3, Orian S. Shirihai3 1Department of Neuroscience, Center for Neuroscience Research, Tufts School of Medicine, 2Department of Internal Medicine, Geriatrics & Gerontology, Wake Forest Baptist Medical Center, 3Department of Medicine, Boston University Medical Center Mitochondrial fusion was measured by tracking the equilibration of photoconverted matrix-targeted GFP across the mitochondrial network over time. Thus far, only one cell could be subjected to an hour long kinetic analysis at a time. We present a method that simultaneously measures multiple cells, thereby speeding up the data collection process. Bioengineering Biomolecular Detection employing the Interferometric Reflectance Imaging Sensor (IRIS) Carlos A. Lopez1, George G. Daaboul2, Sunmin Ahn2, Alexander P. Reddington1, Margo R. Monroe2, Xirui Zhang2, Rostem J. Irani3, Chunxiao Yu4,5, Caroline A. Genco4,5, Marina Cretich6, Marcella Chiari6, Bennett B. Goldberg1, John H. Connor5, M. Selim Ünlü1,2 1Department of Electrical and Computer Engineering, Boston University, 2Department of Biomedical Engineering, Boston University, 3Center for Advanced Genomics Technology, Boston University, 4Department of Medicine, Section of Infectious Diseases, Boston University School of Medicine, 5Department of Microbiology, Boston University School of Medicine, 6CNR (National Research Council), Istituto di Chimica del Riconoscimento Molecolare Quantitative, high-throughput, real-time, and label-free biomolecular detection (DNA, protein, etc.) on SiO2 surfaces can be achieved using a simple interferometric technique which relies on LED illumination, minimal optical components, and a camera. The Interferometric Reflectance Imaging Sensor (IRIS) is inexpensive, simple to use, and amenable to microarray formats. Neuroscience Single-unit In vivo Recordings from the Optic Chiasm of Rat Daniel K. Freeman1, Walter F. Heine1, Christopher L. Passaglia1 1Department of Biomedical Engineering, Boston University Retinal ganglion cells transmit visual information from the eye to the brain with sequences of action potentials. Here, we demonstrate how to record the action potentials of single ganglion cells in vivo from anesthetized rats. Neuroscience A Novel Approach for Documenting Phosphenes Induced by Transcranial Magnetic Stimulation Seth Elkin-Frankston1, Peter J. Fried1, Alvaro Pascual-Leone2, R. J. Rushmore III1, Antoni Valero-Cabré1,3 1Department of Anatomy and Neurobiology, Boston University School of Medicine, 2Department of Neurology, Beth Israel Deaconess Med Center, 3Centre de Recherche de l'institut du Cerveau et la Moelle Epinière (CRICM), Centre National de la Recherche Scientifique (CNRS) Phosphenes are transient percepts of light that can be induced by applying Transcranial Magnetic Stimulation (TMS) to visually sensitive regions of cortex. We demonstrate a standard protocol for determining the phosphene threshold value and introduce a novel method for quantifying and analyzing perceived phosphenes. Biology Automated System for Single Molecule Fluorescence Measurements of Surface-immobilized Biomolecules Nicolas Di Fiori1, Amit Meller1,2 1Physics Department, Boston University, 2Department of Biomedical Engineering, Boston University In this article we describe how we obtain FRET traces from individual DNA molecules immobilized to a surface using an automated scanning confocal microscope. Biology Using the Horseshoe Crab, Limulus Polyphemus, in Vision Research Jiahui S. Liu1, Christopher L. Passaglia1 1Department of Biomedical Engineering, Boston University In this video we perform electroretinogram recording, optic nerve recording, and intraretinal recording with the American horseshoe crab, Limulus Polyphemus. These electrophysiological paradigms can be used for investigating the neural basis of vision in a research or teaching lab. Biology Whole-cell Recordings of Light Evoked Excitatory Synaptic Currents in the Retinal Slice Birgit Werner1, Paul B. Cook1,2, Christopher L. Passaglia1,3 1Program in Neuroscience, Boston University, 2Department of Biology, Boston University, 3Department of Biomedical Engineering, Boston University This video shows the process of whole-cell voltage clamp recordings in the retinal slice of the aquatic tiger salamander. We demonstrate the preparation of the slice as well as how to perform patch clamp recordings during visual stimulation of the retina. Biology Fabrication of the Thermoplastic Microfluidic Channels Arpita Bhattacharyya1, Dominika Kulinski1, Catherine Klapperich1 1Department of Biomedical Engineering, Boston University Here we demonstrate how to fabricate thermoplastic microfluidic chips using hot embossing and heat sealing. Then we demonstrate how to use in situ light directed surface grafting and polymerization through the sealed chip to form the composite solid phase columns. Biology Microfluidic Applications for Disposable Diagnostics Catherine Klapperich1 1Department of Biomedical Engineering, Boston University In this interview, Dr. Klapperich discusses the fabrication of thermoplastic microfluidic devices and their application for development of new diagnostics. Biology Wolbachia Bacterial Infection in Drosophila Horacio Frydman1 1Boston University