title: Characterization of planar concentration gradients in a sequential-injection system for cell-perfusion studies.
abstract: This paper describes the characterization of a perfusion chamber that is coupled with a sequential-injection system and is being designed for live-cell perfusion. The apparatus consists of a multi-port valve, a peristaltic pump, a perfusion chamber and an epifluorescence microscope. The entire system is computer controlled and temperature regulated. The parameters discussed are the concentration-time profiles with regard to the volume of reagent used and the position of the cell in the perfusion chamber. Other parameters discussed include the stopped-flow compliance, reproducibility and symmetry of the concentration gradients formed. The system is shown to be suitable for two modes of perfusion; the first in which all cells are exposed to the same concentration of reagent, and the second in which cells are exposed to a gradient of concentrations. All characterization is performed with use of bulk fluorescein as a tracer, and a correlation is made between the bulk flow and the response within the cellular environment by using 5-[N-(octadecanoyl)amino]fluorescein.
authors.affiliation: Department of Chemistry, University of Washington, Seattle 98195.
authors.forename: C H
authors.initials: CH
authors.lastname: Pollema
authors.forename: J
authors.initials: J
authors.lastname: Růzicka
mesh_terms: D002477:Cells / Q000737:chemistry*; D003584:Cytological Techniques / Q000295:instrumentation*; D017022:Flow Injection Analysis / Q000295:instrumentation / Q000379:methods*; D008856:Microscopy, Fluorescence / Q000379:methods; D010477:Perfusion