California State University, Long Beach 2 articles published in JoVE Developmental Biology Caenorhabditis Sieve: A Low-tech Instrument and Methodology for Sorting Small Multicellular Organisms Skyler Hunter*1,2, Malabika Maulik*3, Courtney Scerbak4, Elena Vayndorf2, Barbara E. Taylor5 1Department of Biology and Wildlife, University of Alaska Fairbanks, 2Institute of Arctic Biology, University of Alaska Fairbanks, 3Department of Chemistry and Biochemistry, University of Alaska Fairbanks, 4Departments of Biology and Chemistry, Earlham College, 5Department of Biological Sciences, College of Natural Science and Mathematics, California State University Long Beach The current protocol includes a methodology for the sorting and cleaning of age-matched populations of Caenorhabditis elegans. It uses a simple, inexpensive, and efficient custom-made tool to obtain a large experimental population of nematodes for research. Bioengineering Planar Gradient Diffusion System to Investigate Chemotaxis in a 3D Collagen Matrix David A. Stout1, Jennet Toyjanova2, Christian Franck3 1Department of Mechanical and Aerospace Engineering, California State University, Long Beach, 2Ximedica, 3School of Engineering, Brown University Cell migration is an important part of human development and life. In order to understand the mechanisms that can alter cell migration, we present a planar gradient diffusion system to investigate chemotaxis in a 3D collagen matrix, which allows one to overcome modern diffusion chamber limitations of existing assays.