Cloaked Exosomes: Biocompatible, Durable, and Degradable Encapsulation. Issue 34 (19th July 2018)

• Record Type: Journal Article
• Authors: Kumar, Sumit; Michael, Issac J.; Park, Juhee; Granick, Steve; Cho, Yoon‐Kyoung
• Is Part Of: Small. Volume 14:Issue 34(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-07-19
• Subjects: exosomes -- nanoencapsulation -- nanofilms -- surface engineering -- tannic acid; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.201802052
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract: Exosomes—nanosized extracellular vesicles (EVs) naturally secreted from cells—have emerged as promising biomarkers and potential therapeutic vehicles, but methods to manipulate them for engineering purposes remain elusive. Among the technical obstacles are the small size and surface complexity of exosomes and the complex processing steps required, which reduce the biocompatibility of currently available methods. The encapsulation of exosomes with a nanofilm of supramolecular complexes of ferric ions (Fe 3+ ) and tannic acid is demonstrated here. The resulting natural polyphenol, ≈10 nm thick, protects exosomes from external aggressors such as UV‐C irradiation or heat and is controllably degraded on demand. Furthermore, gold nanoparticles can be covalently attached for single‐exosome level visualization. To fully exploit their therapeutic potential, chemotherapeutic drug‐loaded EVs are functionalized to achieve the targeted, selective killing of cancer cells preferentially over normal cells. This nanofilm not only preserves the native size and chemical makeup of the intrinsic exosomes, but also confers new capabilities for efficient tumor targeting and pH‐controlled release of drugs. Demonstrating a scalable method to produce biocompatible, durable, on‐demand degradable, and chemically controllable shields for exosome modification and functionalization, the methods introduced here are expected to bring the potential of exosome‐based nanomedicine applications closer to reality. Abstract : Exosomes are encapsulated with a nanofilm by rapid mixing of ferric ion and tannic acid at a microfluidic T‐junction in water‐in‐oil droplet reactors, which protect them against external stress, especially UV irradiation and elevated temperature. On‐demand chemical degradation and further surface functionalization capabilities open up new applications beyond their native functions.