Stimuli-responsive plasmonic core–satellite assemblies: i-motif DNA linker enabled intracellular pH sensing

Abstract

We report stimuli-responsive core-satellite assemblies of binary gold nanoparticles, linked by i-motif DNA, for live cell plasmonic imaging of pH changes in the endocytic pathway.

Controlling DNA–nanoparticle serum interactions

“…Applying these design criteria to engineer DNA-assembled nanoparticles, we showed assembled structures with tunable serum stability ranging from 0.1 to 0.7 h −1 in addition to structures capable of releasing two model drugs at distinct kinetics. In future work, we plan to explore these engineering principles for multidrug of this study offer useful information for designing DNA-assembled nanoparticles for in vivo applications (2,5) and show an experimental framework that could be applied to investigate serum stability of other types of DNA nanostructures (45,46).…”

“…DNA-assembled nanoparticles retain their large surface area to volume ratios for functionalization with molecular payload (8,9) and can be designed to generate novel properties that derive from particle-particle coupling (10,11). DNA-assembled nanoparticle systems are highly modular, allowing combinations of varying nanoparticle compositions, surface coatings, and assembly architectures to be rapidly prototyped and evaluated for their biological properties and applications (5,12,13). Finally, biodegradation of DNA results in nanoparticle disassembly and release of tethered components, which provides a natural mechanism for bioelimination and/or drug release (2).…”

“…One emergent concept is the need for dynamic nanoparticle systems that are capable of changing their physicochemical properties within the physiological environment (1)(2)(3). This idea builds on the culmination of experimental evidence showing that cells and tissues interact with engineered nanoparticles as a function of their size, shape, and surface chemistry (4) but that these parameters must adapt to the evolution of in vivo barriers that nanoparticles encounter en route to their intended destination (2,5).…”

DNA i-motif provides steel-like tough ends to chromosomes

“…However, i-motif tetramers have also been observed in vivo, most notably in the terminal part of the human genes, or telomere, where rather long (50-210 bases) asymmetric G-rich and C-rich single-stranded portions of DNA are found [5,6]. Besides their possible role in the genome, still awaiting a full clarification, such DNA nanowires can be also attractive in the domain of bio-inspired materials for nanotechnologies [7][8][9][10]. Notably, various kinds of biomimetic nanowires have been already obtained from B-DNA, proteins, and even from viral particles.…”

Plasmonic Core–Satellite Assemblies as Highly Sensitive Refractive Index Sensors

“…5 Moreover, the resonance wavelength of core-satellites can be tuned from 543 nm to 575 nm by adjusting the number of satellites. These nanostructures will be useful for various plasmonic applications like SERS, 13 multiplexed analyte detection 14 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 3 Controlled assembly of gold nanoparticles into dimers, 16 trimers 17 and core-satellites 18,19 is an effective means to increase 20 their Raman scattering enhancement by a factor of 10 8 -10 11 . The accepted reason is that these nanostructures have sharper apexes and a gap which allow a large part of the plasmon field to penetrate the dielectric environment.…”