title: Long-term imaging of Caenorhabditis elegans using nanoparticle-mediated immobilization.
abstract: One advantage of the nematode Caenorhabditis elegans as a model organism is its suitability for in vivo optical microscopy. Imaging C. elegans often requires animals to be immobilized to avoid movement-related artifacts. Immobilization has been performed by application of anesthetics or by introducing physical constraints using glue or specialized microfluidic devices. Here we present a method for immobilizing C. elegans using polystyrene nanoparticles and agarose pads. Our technique is technically simple, does not expose the worm to toxic substances, and allows recovery of animals. We evaluate the method and show that the polystyrene beads increase friction between the worm and agarose pad. We use our method to quantify calcium transients and long-term regrowth in single neurons following axotomy by a femtosecond laser.
authors.affiliation: Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America.
authors.forename: Eric
authors.initials: E
authors.lastname: Kim
authors.forename: Lin
authors.initials: L
authors.lastname: Sun
authors.forename: Christopher V
authors.initials: CV
authors.lastname: Gabel
authors.forename: Christopher
authors.initials: C
authors.lastname: Fang-Yen
mesh_terms: D000818:Animals; D019771:Axotomy / Q000295:instrumentation / Q000379:methods; D017173:Caenorhabditis elegans / Q000378:metabolism*; D020013:Calcium Signaling; D007103:Immobilization / Q000295:instrumentation / Q000379:methods*; D046210:Microfluidic Analytical Techniques; D008853:Microscopy / Q000379:methods*; D009068:Movement; D053758:Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D009474:Neurons / Q000378:metabolism; D011137:Polystyrenes / Q000737:chemistry; D012685:Sepharose / Q000737:chemistry
chemical_list: D011137:Polystyrenes; D012685:Sepharose