title: Stimuli-responsive theragrippers for chemomechanical controlled release.
abstract: We report on a therapeutic approach using thermo-responsive multi-fingered drug eluting devices. These therapeutic grippers referred to as theragrippers are shaped using photolithographic patterning and are composed of rigid poly(propylene fumarate) segments and stimuli-responsive poly(N-isopropylacrylamide-co-acrylic acid) hinges. They close above 32 °C allowing them to spontaneously grip onto tissue when introduced from a cold state into the body. Due to porosity in the grippers, theragrippers could also be loaded with fluorescent dyes and commercial drugs such as mesalamine and doxorubicin, which eluted from the grippers for up to seven days with first order release kinetics. In an in vitro model, theragrippers enhanced delivery of doxorubicin as compared to a control patch. We also released theragrippers into a live pig and visualized release of dye in the stomach. The design of such tissue gripping drug delivery devices offers an effective strategy for sustained release of drugs with immediate applicability in the gastrointestinal tract.
authors.affiliation: Department of Chemical and Biomolecular Engineering The Johns Hopkins University 3400 N. Charles St., Baltimore, MD 21218 (USA).
authors.forename: Kate
authors.initials: K
authors.lastname: Malachowski
authors.affiliation: Department of Chemical and Biomolecular Engineering The Johns Hopkins University 3400 N. Charles St., Baltimore, MD 21218 (USA).
authors.forename: Joyce
authors.initials: J
authors.lastname: Breger
authors.affiliation: Department of Chemical and Biomolecular Engineering The Johns Hopkins University 3400 N. Charles St., Baltimore, MD 21218 (USA).
authors.forename: Hye Rin
authors.initials: HR
authors.lastname: Kwag
authors.affiliation: Fischell Department of Bioengineering University of Maryland, College Park, MD 20742 (USA).
authors.forename: Martha O
authors.initials: MO
authors.lastname: Wang
authors.affiliation: Fischell Department of Bioengineering University of Maryland, College Park, MD 20742 (USA).
authors.forename: John P
authors.initials: JP
authors.lastname: Fisher
authors.affiliation: Department of Medicine, The Johns Hopkins University, Baltimore, MD21218 (USA).
authors.forename: Florin M
authors.initials: FM
authors.lastname: Selaru
authors.affiliation: Department of Chemical and Biomolecular Engineering The Johns Hopkins University 3400 N. Charles St., Baltimore, MD 21218 (USA).
authors.forename: David H
authors.initials: DH
authors.lastname: Gracias
mesh_terms: D016503:Drug Delivery Systems; D006358:Hot Temperature
keywords: actuators; drug delivery; hydrogels; polymers; soft robotics