title: Alginate bead fabrication and encapsulation of living cells under centrifugally induced artificial gravity conditions.
abstract: This study presents a novel method for the direct, centrifugally induced fabrication of small, Ca2+-hardened alginate beads at polymer-tube micronozzles. The bead diameter can arbitrarily be adjusted between 180-800 microm by the nozzle geometry and spinning frequencies between 5-28 Hz. The size distribution of the main peak features a CV of 7-16%, only. Up to 600 beads per second and channel are issued from the micronozzle through an air gap towards the curing agent contained in a standard lab tube ('Eppi'). Several tubes can be mounted on a 'flying bucket' rotor where they align horizontally under rotation and return to a vertical position as soon as the rotor is at rest. The centrifugally induced, ultra-high artificial gravity conditions (up to 180 g) even allow the micro-encapsulation of alginate solutions displaying viscosities up to 50 Pa s, i.e. approximately 50,000 times the viscosity of water! With this low cost technology for microencapsulation, HN25 and PC12 cells have successfully been encapsulated while maintaining vitality.
authors.affiliation: HSG-IMIT-Institute for Micromachining and Information Technology, Villingen-Schwenningen, Germany. stefan.haeberle@hsg-imit.de
authors.forename: Stefan
authors.initials: S
authors.lastname: Haeberle
authors.forename: Lars
authors.initials: L
authors.lastname: Naegele
authors.forename: Robert
authors.initials: R
authors.lastname: Burger
authors.forename: Felix
authors.initials: F
authors.lastname: von Stetten
authors.forename: Roland
authors.initials: R
authors.lastname: Zengerle
authors.forename: Jens
authors.initials: J
authors.lastname: Ducrée
mesh_terms: D000313:Adrenal Medulla / Q000166:cytology; D000464:Alginates; D000818:Animals; D002460:Cell Line; D002470:Cell Survival; D019439:Chromaffin Cells / Q000637:transplantation*; D004339:Drug Compounding / Q000379:methods*; D020723:Glucuronic Acid; D006603:Hexuronic Acids; D006624:Hippocampus / Q000166:cytology; D051379:Mice; D009474:Neurons / Q000637:transplantation*; D051381:Rats
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D020723:Glucuronic Acid