MOF-Based Erodible System for On-Demand Release of Bioactive Flavonoid at the Polymer–Tissue Interface

Abstract

Plant-derived compounds incite applications virtually on every biomedical field due to the expedient antioxidant, anti-inflammatory and antimicrobial properties in conjunction with a natural character. Here, quercetin (QCT), a flavonoid with therapeutic potentials relevant to the oral environment, was encapsulated within metal–organic frameworks (MOFs) to address the concept of on-demand release of phytochemicals at the biointerface. We verified the applicability of a microporous MOF (ZIF-8) as a controlled-release system for QCT, as well as investigated the incorporation of QCT@ZIF-8 microparticles into a dental adhesive resin for desirable therapeutic capabilities at the tooth–restoration interface. QCT was encapsulated within the frameworks through a water-based, one-step synthetic process. The resulting QCT@ZIF-8 microparticles were characterized with respect to chemical composition, crystal structure, thermal behavior, micromorphology, and release profile under acidic and physiological conditions. A model dental adhesive formulation was enriched with the bioactive microparticles; both the degree of conversion (DC) of methacrylic double bonds and the polymer thermal behavior were accounted for. The results confirm that crystalline QCT@ZIF-8 microparticles with attractive loading capacities, submicron sizes, high thermal stability and responsiveness to environmental pH change were successfully manufactured. The concentration of QCT@ZIF-8 in the resin system was a key factor to maintain an optimal DC plateau and rate of polymerization. Essentially, one-step encapsulation of QCT in biocompatible ZIF-8 matrices can be easily achieved, and QCT@ZIF-8 microparticles proved as smart platforms to carry bioactive compounds with potential use to prevent microbial and enzymatic degradation of hard tissues and extracellular matrix components.

Telescopic synthesis and encapsulation of anticancer drugs from Ajuga bracteosa Wall. ex Benth. with zeolitic imidazole framework‐8

“…The simulated ZIF-8 and cubic unit cell agree well with the ZIF-8 and ABE@ZIF-8 peaks (JCPDS 00-062-1030 confirms it; a = b = c = 17.0116 and α = β = γ = 90 ). [41] The ZIF-8 crystal diffractions agreed well with the characteristic peaks of a simulated pattern from the published ZIF-8 crystal structure, and the peaks of ZIF-8 and ABE@ZIF-8 are very similar.…”

Biomimetic Growth of Metal–Organic Frameworks for the Stabilization of the Dentin Matrix and Control of Collagenolysis

“…, enzyme inhibitors, antibodies, etc. ) , incorporated within the porous network directly to the extracellular space.…”

“…The tunable biodegradability of ZIF-8 could enable the controlled release of drugs (e.g., enzyme inhibitors, antibodies, etc.) 53,54 incorporated within the porous network directly to the extracellular space.…”

Hierarchical porous metal–organic gels and derived materials: from fundamentals to potential applications

“…ZIF-8-based carrier encapsulating quercetin, a flavonoid with therapeutic potential in the oral environment, was also devised and encapsulated into a dental adhesive resin forming nanocomposite release system at the tooth–restoration interface. 355 The platform also responded to pH changes, and prevented microbial infiltration, as well as enzymatic degradation of surrounding hard tissues and extracellular matrix components, thereby restoring the homeostasis of the oral tissue area. The release occurred upon pH-driven degradation of MOF cages via bacterial released lactic acids from cariogenic biofilms.…”