title: Stop-flow lithography for the production of shape-evolving degradable microgel particles.
abstract: Microgel particles capable of bulk degradation have been synthesized from a solution of diacrylated triblock copolymer composed of poly(ethylene glycol) and poly(lactic acid) in a microfluidic device using stop-flow lithography (SFL). It has been previously demonstrated that SFL can be used to fabricate particles with precise control over particle size and shape. Here, we have fabricated hydrogel particles of varying size and shape and examined their mass-loss and swelling behavior histologically and mechanically. We report that these features, as well as degradation behavior of the hydrogel particles may be tailored with SFL. By reducing the applied UV dose during fabrication, hydrogel particles can be made to exhibit a distinct deviation from the classical erosion profiles of bulk-degrading hydrogels. At higher UV doses, a saturation in cross-linking density occurs and bulk-degrading behavior is observed. Finally, we synthesized multifunctional composite particles, providing unique features not found in homogeneous hydrogels.
authors.affiliation: Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: Dae Kun
authors.initials: DK
authors.lastname: Hwang
authors.forename: John
authors.initials: J
authors.lastname: Oakey
authors.forename: Mehmet
authors.initials: M
authors.lastname: Toner
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Arthur
authors.forename: Kristi S
authors.initials: KS
authors.lastname: Anseth
authors.forename: Sunyoung
authors.initials: S
authors.lastname: Lee
authors.forename: Adam
authors.initials: A
authors.lastname: Zeiger
authors.forename: Krystyn J
authors.initials: KJ
authors.lastname: Van Vliet
authors.forename: Patrick S
authors.initials: PS
authors.lastname: Doyle
mesh_terms: D001672:Biocompatible Materials; D016503:Drug Delivery Systems; D020100:Hydrogels / Q000737:chemistry* / Q000378:metabolism; D019344:Lactic Acid / Q000737:chemistry; D008422:Materials Testing; D046210:Microfluidic Analytical Techniques; D044085:Microfluidics; D010316:Particle Size; D055585:Physical Phenomena; D011091:Polyesters; D011092:Polyethylene Glycols / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D013696:Temperature; D023822:Tissue Engineering
chemical_list: D001672:Biocompatible Materials; D020100:Hydrogels; D011091:Polyesters; D011108:Polymers; D019344:Lactic Acid; D011092:Polyethylene Glycols; C033616:poly(lactide)