title: Micro-particle transporting system using galvanotactically stimulated apo-symbiotic cells of Paramecium bursaria.
abstract: It is well known that Paramecium species including green paramecia (Paramecium bursaria) migrate towards the anode when exposed to an electric field in a medium. This type of a cellular movement is known as galvanotaxis. Our previous study revealed that an electric stimulus given to P bursaria is converted to a galvanotactic cellular movement by involvement of T-type calcium channel on the plasma membrane [Aonuma et al. (2007), Z. Naturforsch. 62c, 93-102]. This phenomenon has attracted the attention of bioengineers in the fields of biorobotics or micro-robotics in order to develop electrically controllable micromachineries. Here, we demonstrate the galvanotactic controls of the cellular migration of P bursaria in capillary tubes (diameter, 1-2 mm; length, 30-240 mm). Since the Paramecium cells take up particles of various sizes, we attempted to use the electrically stimulated cells of P bursaria as the vehicle for transportation of micro-particles in the capillary system. By using apo-symbiotic cells of P bursaria obtained after forced removal of symbiotic algae, the uptake of the particles could be maximized and visualized. Then, electrically controlled transportations of particle-filled apo-symbiotic P bursaria cells were manifested. The particles transported by electrically controlled cells (varying in size from nm to /m levels) included re-introduced green algae, fluorescence-labeled polystyrene beads, magnetic microspheres, emerald green fluorescent protein (EmGFP)-labeled cells of E. coli, Indian ink, and crystals of zeolite (hydrated aluminosilicate minerals with a micro-porous structure) and some metal oxides. Since the above demonstrations were successful, we concluded that P bursaria has a potential to be employed as one of the micro-biorobotic devices used in BioMEMS (biological micro-electro-mechanical systems).
authors.affiliation: Faculty and Graduate School of Environmental Engineering, The University of Kitakyushu, Kitakyushu 808-0135, Japan.
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Furukawa
authors.forename: Chiaki
authors.initials: C
authors.lastname: Karaki
authors.forename: Tomonori
authors.initials: T
authors.lastname: Kawano
mesh_terms: D000818:Animals; D002452:Cell Count; D002460:Cell Line; D002465:Cell Movement; D000460:Chlorophyta / Q000502:physiology; D002923:Cilia / Q000502:physiology; D004558:Electric Stimulation; D056890:Eukaryota / Q000502:physiology; D010247:Paramecium / Q000166:cytology / Q000502:physiology*; D013559:Symbiosis / Q000502:physiology*