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Ruthenium-Crosslinked Hydrogels with Rapid, Visible-Light Degradation.

ABSTRACT: Incorporation of photoresponsive molecules within soft materials can provide spatiotemporal control over bulk properties and address challenges in targeted delivery and mechanical variability. However, the kinetics of in situ photochemical reactions are often slow and typically employ ultraviolet wavelengths. Here, we present a novel photoactive crosslinker Ru(bipyridine)2 (3-pyridinaldehyde)2 (RuAldehyde), which was reacted with hydrazide-functionalized hyaluronic acid to form hydrogels capable of encapsulating protein cargo. Visible light irradiation (400-500?nm) initiated rapid ligand exchange on the ruthenium center, which degraded the hydrogel within seconds to minutes, depending on gel thickness. An exemplar enzyme cargo, TEM1 ?-lactamase, was loaded into and photoreleased from the Ru-hydrogel. To expand their applications, Ru-hydrogels were also processed into microgels using a microfluidic platform.

SUBMITTER: Rapp TL

PROVIDER: S-EPMC5915374 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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Ruthenium-Crosslinked Hydrogels with Rapid, Visible-Light Degradation.

Rapp Teresa L TL Highley Christopher B CB Manor Brian C BC Burdick Jason A JA Dmochowski Ivan J IJ

Chemistry (Weinheim an der Bergstrasse, Germany) 20180110 10

Incorporation of photoresponsive molecules within soft materials can provide spatiotemporal control over bulk properties and address challenges in targeted delivery and mechanical variability. However, the kinetics of in situ photochemical reactions are often slow and typically employ ultraviolet wavelengths. Here, we present a novel photoactive crosslinker Ru(bipyridine)<sub>2</sub> (3-pyridinaldehyde)<sub>2</sub> (RuAldehyde), which was reacted with hydrazide-functionalized hyaluronic acid to ...[more]

PMID: 29161461

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