One‐Step Labeling of Collagen Hydrogels with Polydopamine and Manganese Porphyrin for Non‐Invasive Scaffold Tracking on Magnetic Resonance Imaging

• Published in: Macromolecular bioscience Vol. 19; no. 4; pp. e1800330 - n/a
• Main Authors: Szulc, Daniel Andrzej, Cheng, Hai‐Ling Margaret
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01-04-2019
• Subjects: biomaterial; Biomaterials; biomedical engineering; Biomedical materials; Collagen; Design optimization; Hydrogels; Image contrast; In vivo methods and tests; Labeling; Magnetic resonance imaging; Manganese; NMR; Nuclear magnetic resonance; Organic chemistry; Regeneration; scaffold monitoring; Scaffolds; tissue engineering; Tracking; magnetic resonance imaging; tissue engineering; biomaterial; biomedical engineering; scaffold monitoring
• ISSN: 1616-5187; 1616-5195
• DOI: 10.1002/mabi.201800330

Biomaterial scaffolds are the cornerstone to supporting 3D tissue growth. Optimized scaffold design is critical to successful regeneration, and this optimization requires accurate knowledge of the scaffold's interaction with living tissue in the dynamic in vivo milieu. Unfortunately, non‐invasive methods that can probe scaffolds in the intact living subject are largely underexplored, with imaging‐based assessment relying on either imaging cells seeded on the scaffold or imaging scaffolds that have been chemically altered. In this work, the authors develop a broadly applicable magnetic resonance imaging (MRI) method to image scaffolds directly. A positive‐contrast “bright” manganese porphyrin (MnP) agent for labeling scaffolds is used to achieve high sensitivity and specificity, and polydopamine, a biologically derived universal adhesive, is employed for adhering the MnP. The technique was optimized in vitro on a prototypic collagen gel, and in vivo assessment was performed in rats. The results demonstrate superior in vivo scaffold visualization and the potential for quantitative tracking of degradation over time. Designed with ease of synthesis in mind and general applicability for the continuing expansion of available biomaterials, the proposed method will allow tissue engineers to assess and fine‐tune the in vivo behavior of their scaffolds for optimal regeneration.
Magnetic resonance imaging (MRI) “trackable” collagen hydrogels are created with a facile, one‐pot synthesis that can be extended to a variety of other materials relevant in tissue engineering applications. These functionalized scaffolds exhibit biocompatibility and considerable contrast enhancement on MRI, and permit non‐invasive in vivo tracking until near complete scaffold degradation.