title: A bio-inspired swellable microneedle adhesive for mechanical interlocking with tissue.
abstract: Achieving significant adhesion to soft tissues while minimizing tissue damage poses a considerable clinical challenge. Chemical-based adhesives require tissue-specific reactive chemistry, typically inducing a significant inflammatory response. Staples are fraught with limitations including high-localized tissue stress and increased risk of infection, and nerve and blood vessel damage. Here inspired by the endoparasite Pomphorhynchus laevis, which swells its proboscis to attach to its host's intestinal wall, we have developed a biphasic microneedle array that mechanically interlocks with tissue through swellable microneedle tips, achieving ~3.5-fold increase in adhesion strength compared with staples in skin graft fixation, and removal force of ~4.5 N cm(-2) from intestinal mucosal tissue. Comprising a poly(styrene)-block-poly(acrylic acid) swellable tip and non-swellable polystyrene core, conical microneedles penetrate tissue with minimal insertion force and depth, yet high adhesion strength in their swollen state. Uniquely, this design provides universal soft tissue adhesion with minimal damage, less traumatic removal, reduced risk of infection and delivery of bioactive therapeutics.
authors.affiliation: Division of Biomedical Engineering, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.
authors.forename: Seung Yun
authors.initials: SY
authors.lastname: Yang
authors.forename: Eoin D
authors.initials: ED
authors.lastname: O'Cearbhaill
authors.forename: Geoffroy C
authors.initials: GC
authors.lastname: Sisk
authors.forename: Kyeng Min
authors.initials: KM
authors.lastname: Park
authors.forename: Woo Kyung
authors.initials: WK
authors.lastname: Cho
authors.forename: Martin
authors.initials: M
authors.lastname: Villiger
authors.forename: Brett E
authors.initials: BE
authors.lastname: Bouma
authors.forename: Bohdan
authors.initials: B
authors.lastname: Pomahac
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Karp
mesh_terms: D000269:Adhesives; D009339:Needles
chemical_list: D000269:Adhesives