Thermoplasmonic‐Triggered Release of Loads from DNA‐Modified Hydrogel Microcapsules Functionalized with Au Nanoparticles or Au Nanorods

Abstract

Microcapsules consisting of hydrogel shells cross‐linked by glucosamine–boronate ester complexes and duplex nucleic acids, loaded with dyes or drugs and functionalized with Au nanoparticles (Au NPs) or Au nanorods (Au NRs), are developed. Irradiation of Au NPs or Au NRs results in the thermoplasmonic heating of the microcapsules, and the dissociation of the nucleic acid cross‐linkers. The separation of duplex nucleic acid cross‐linkers leads to low‐stiffness hydrogel shells, allowing the release of loads. Switching off the light‐induced plasmonic heating results in the regeneration of stiff hydrogel shells protecting the microcapsules, leading to the blockage of release processes. The thermoplasmonic release of tetramethylrhodamine‐dextran, Texas Red‐dextran, doxorubicin‐dextran (DOX‐D), or camptothecin‐carboxymethylcellulose (CPT‐CMC) from the microcapsules is introduced. By loading the microcapsules with two different drugs (DOX‐D and CPT‐CMC), the light‐controlled dose release is demonstrated. Cellular experiments show efficient permeation of Au NPs/DOX‐D or Au NRs/DOX‐D microcapsules into MDA‐MB‐231 cancer cells and inefficient uptake by MCF‐10A epithelial breast cells. Cytotoxicity experiments reveal selective thermoplasmon‐induced cytotoxicity of the microcapsules toward MDA‐MB‐231 cancer cells as compared to MCF‐10A cells. Also, selective cytotoxicity towards MDA‐MB‐231 cancer cells upon irradiation of the Au NPs‐ and Au NRs‐functionalized microcapsules at λ = 532 or 910 nm is demonstrated.

Stimuli‐Responsive Nanocomposite Hydrogels for Biomedical Applications

“…Alternatively, DNA‐based hydrogel compartments (built from synthetic DNA duplex) incorporating gold nanomaterials (i.e., nanorods or nanoparticles) can also attain light‐responsive intermittent payload delivery, due to dehybridization of duplex nucleic acid units resulting from gold thermoplasmonic heating. [ 140 ] Moreover, mild temperature increases can intrinsically induce dynamic bonding, which in hybrid networks containing photothermal nanomaterials as transducers can be exploited to accelerate self‐healing kinetics in a spatiotemporally controlled manner. Regarding this, nanocomposite hydrogels comprised by dynamic thiolate‐gold nanoparticle crosslinking showcased that damaged constructs could be instructed to rapidly self‐heal upon focused NIR laser irradiation due to switching on its reversible bonding character.…”

Aptamer-Functionalized Hybrid Nanostructures for Sensing, Drug Delivery, Catalysis and Mechanical Applications

“…Nucleic acid structures have been often used as caging units of drug carriers that can be unlocked by nucleic acid biomarkers such as miRNAs [ 137 ], the pH-induced separation of DNA locks via the dissociation of i-motifs [ 138 , 139 ] or triplexes, [ 140 , 141 ] the separation of K + -ion stabilized G-quadruplex locks by crown ether [ 142 , 143 ], and the degradation of DNA locks by enzymes [ 144 ] or DNAzymes [ 145 ]. Physical triggers, such as heat [ 146 , 147 , 148 ] or light [ 149 , 150 , 151 , 152 , 153 ] have also been used to uncage DNA-gated carriers. The sequence-specific recognition properties of aptamer-ligand complex have been extensively used to design nucleic acid-based gating units being unlocked through the formation of aptamer-ligand complexes [ 154 ].…”

Choice of fluorophore affects dynamic DNA nanostructures

“…DNA nanotechnology has been highly successful in repurposing the iconic DNA double helix to create programmable molecular architectures. Once focused on static shapes, dynamic and stimuli-responsive DNA nanoscale devices are gaining a large surge of interest for various applications ( 1 )—from sensors ( 2–4 ), biocomputing algorithms ( 5 ), and drug delivery systems ( 6 , 7 ) to programmable robotic modules ( 8 , 9 ) and functional components for synthetic cells ( 10–12 ). In a vast majority of such reconfigurable systems, dynamics are achieved using strand displacement reactions ( 13 , 14 ), flexible single-stranded hinges ( 15 ), stimuli-responsive DNA modifications ( 16 , 17 ) or sequence motifs ( 4 , 18 ).…”