title: Silk-based biomaterials for sustained drug delivery.
abstract: Silk presents a rare combination of desirable properties for sustained drug delivery, including aqueous-based purification and processing options without chemical cross-linkers, compatibility with common sterilization methods, controllable and surface-mediated biodegradation into non-inflammatory by-products, biocompatibility, utility in drug stabilization, and robust mechanical properties. A versatile silk-based toolkit is currently available for sustained drug delivery formulations of small molecule through macromolecular drugs, with a promise to mitigate several drawbacks associated with other degradable sustained delivery technologies in the market. Silk-based formulations utilize silk's well-defined nano- through microscale structural hierarchy, stimuli-responsive self-assembly pathways and crystal polymorphism, as well as sequence and genetic modification options towards targeted pharmaceutical outcomes. Furthermore, by manipulating the interactions between silk and drug molecules, near-zero order sustained release may be achieved through diffusion- and degradation-based release mechanisms. Because of these desirable properties, there has been increasing industrial interest in silk-based drug delivery systems currently at various stages of the developmental pipeline from pre-clinical to FDA-approved products. Here, we discuss the unique aspects of silk technology as a sustained drug delivery platform and highlight the current state of the art in silk-based drug delivery. We also offer a potential early development pathway for silk-based sustained delivery products.
authors.affiliation: Tufts University, Department of Biomedical Engineering, Medford, MA 02155, USA; Ekteino Laboratories, New York, NY 10022, USA.
authors.forename: Tuna
authors.initials: T
authors.lastname: Yucel
authors.affiliation: Tufts University, Department of Biomedical Engineering, Medford, MA 02155, USA; Ekteino Laboratories, New York, NY 10022, USA.
authors.forename: Michael L
authors.initials: ML
authors.lastname: Lovett
authors.affiliation: Tufts University, Department of Biomedical Engineering, Medford, MA 02155, USA.
authors.forename: David L
authors.initials: DL
authors.lastname: Kaplan
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D003692:Delayed-Action Preparations; D016503:Drug Delivery Systems; D004355:Drug Stability; D006801:Humans; D020100:Hydrogels / Q000737:chemistry; D047011:Silk / Q000737:chemistry* / Q000493:pharmacokinetics
chemical_list: D001672:Biocompatible Materials; D003692:Delayed-Action Preparations; D020100:Hydrogels; D047011:Silk
keywords: Biocompatibility; Biodegradation; Biologics; Drugs; Mechanisms; Processing