title: Electrokinetically controlled fluid injection into unicellular microalgae.
abstract: Electrokinetically controlled microinjection is reported as an effective transport mechanism for microinjection into the wild-type strain of the widely studied model microalga Chlamydomonas reinhardtii. A microinjection system using glass capillary pipettes was developed to capture and impale the motile cells. To apply an electric field and induce electrokinetic flow (e.g., electrophoresis and electroosmosis), an electrode was inserted directly into the solution inside the impaling injection pipette and another electrode was inserted into the external cell media. The viability of the impaled cells was confirmed for more than an hour under 0.01 V using the fluorescein diacetate/propidium iodide dual fluorescent dye based assay. The viability was also found to increase almost logarithmically with decreasing voltage and to depend strongly on the solution within the injection pipette. Successful electrokinetic microinjection into cells was confirmed by both an increase in cell volume under an applied voltage and electric field dependent delivery of fluorescent fluorescein molecules into an impaled cell. Our study offers novel opportunities for quantitative delivery of biomolecules into microalgae and advancing the research and development of these organisms as biosynthetic factories.
authors.affiliation: Department of Chemical Engineering, University of Rochester, Rochester, NY, USA.
authors.forename: Xuewen
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Department of Chemical Engineering, University of Rochester, Rochester, NY, USA.
authors.forename: Xixi
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Chemical Engineering, University of Rochester, Rochester, NY, USA.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Boualavong
authors.affiliation: Department of Chemical Engineering, University of Rochester, Rochester, NY, USA.
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Durney
authors.affiliation: Department of Chemical Engineering, University of Rochester, Rochester, NY, USA.
authors.forename: Tonghui
authors.initials: T
authors.lastname: Wang
authors.affiliation: Department of Chemical Engineering, University of Rochester, Rochester, NY, USA.
authors.forename: Scott
authors.initials: S
authors.lastname: Kirschner
authors.affiliation: Department of Chemical Engineering, University of Rochester, Rochester, NY, USA.
authors.forename: Michaela
authors.initials: M
authors.lastname: Wentz
authors.affiliation: Department of Chemical Engineering, University of Rochester, Rochester, NY, USA.
authors.forename: Hitomi
authors.identifier: 0000-0001-7195-6403
authors.initials: H
authors.lastname: Mukaibo
mesh_terms: D003198:Computer Simulation; D004560:Electricity; D053841:Electroosmosis; D004586:Electrophoresis / Q000295:instrumentation*; D007700:Kinetics; D058086:Microalgae / Q000737:chemistry*; D046210:Microfluidic Analytical Techniques; D008845:Microinjections / Q000295:instrumentation*
keywords: Electroosmosis; Electrophoresis; Microalgae; Microinjection; Numerical analyses