Aqueous Stable Gold Nanostar/ZIF‐8 Nanocomposites for Light‐Triggered Release of Active Cargo Inside Living Cells

Abstract

A plasmonic core–shell gold nanostar/zeolitic‐imidazolate‐framework‐8 (ZIF‐8) nanocomposite was developed for the thermoplasmonic‐driven release of encapsulated active molecules inside living cells. The nanocomposites were loaded, as a proof of concept, with bisbenzimide molecules as functional cargo and wrapped with an amphiphilic polymer that prevents ZIF‐8 degradation and bisbenzimide leaking in aqueous media or inside living cells. The demonstrated molecule‐release mechanism relies on the use of near‐IR light coupled to the plasmonic absorption of the core gold nanostars, which creates local temperature gradients and thus, bisbenzimide thermodiffusion. Confocal microscopy and surface‐enhanced Raman spectroscopy (SERS) were used to demonstrate bisbenzimide loading/leaking and near‐IR‐triggered cargo release inside cells, thereby leading to DNA staining.

Core-Shell Palladium/MOF Platforms as Diffusion-Controlled Nanoreactors in Living Cells and Tissue Models

“…Taking geometrical and structural considerations regarding the Pd-NPs used herein, 56 , 63 we estimate that ∼5% of the Pd content of one Pd-NP are surface atoms (surface Pd) and thereby potentially available for the catalytic processes ( Table S4 ). Importantly, although the specific surface area of the NRs decreases after PMA-modification, 55 likely because the PMA partially fills voids in the nanostructure, the ZIF-8 shell remains porous and accessible for small molecule loading by diffusion, as demonstrated with model fluorescent probes ( Table S5 ; Figure S14 ).…”

“…The PMA derivatization strategy renders the nanocomposite stable in aqueous media. 55 Importantly, we demonstrate that the ZIF-8/PMA architecture not only protects the Pd nanocatalyst from deactivation, leaking, and aggregation, but its porosity allows a diffusion-controlled flow of reactants within the core reaction chamber ( Figure 1 A). As a result, these constructs can be used as efficient metallo-nanoreactors (NRs) in complex aqueous media and inside living mammalian cells.…”

“…(2) These Pd-NPs were then used as seeds onto which a shell of ZIF-8 was grown by following an aqueous procedure in which the surfactant CTAB works as size-controlling and structural-directing agent. (3) Finally, in order to provide colloidal stability in diverse complex aqueous media, these Pd/ZIF-8 core-shell particles were wrapped with the amphiphilic polymer PMA by following a recently described protocol; 55 alternatively, PMA was covalently modified with a rhodamine (specifically, we used 5(6)-TAMRA cadaverine) for fluorescence labeling of our NRs, as previously reported for analogous plasmonic nanocomposites. 55 …”

A shape memory porous sponge with tunability in both surface wettability and pore size for smart molecule release

“…The obtained SMS has so distinguished controllability in water permeation based on excellent tunability in both pore size and surface wettability, indicating that it can be applied in various research areas, for instance as a system for adjusting the small molecule release. Nowadays, porous materials with adjustable small molecule release property have aroused great interest [60][61][62] [63][64][65]. Herein, based on our sponge, diverse release manners can be achieved.…”

Plasmonic metal‐organic frameworks

“…The lack of stability of the ZIF‐8 matrix in the biological medium can be enhanced by coating with an amphiphilic polymer shell 117 . Thus, highly stable thermoresponsive plasmonic nanocarriers were obtained by coating Au nanostar@ZIF‐8 core–shell nanostructures with poly[isobutylene‐alt‐maleic anhydride]‐graft‐dodecyl (PMA) 118 . The polymer shell provided stability to the MOF matrix, while activating cargo release inside living cells upon plasmon excitation.…”