Current nucleic acid delivery methods have not achieved efficient, non‐toxic delivery of miRNAs with tumor‐specific selectivity. In this study, a new delivery system based on light‐inducible gold–silver–gold, core–shell–shell (CSS) nanoparticles is presented. This system delivers small nucleic acid therapeutics with precise spatiotemporal control, demonstrating the potential for achieving tumor‐specific selectivity and efficient delivery of miRNA mimics. The light‐inducible particles leverage the photothermal heating of metal nanoparticles due to the local surface plasmonic resonance for controlled chemical cleavage and release of the miRNA mimic payload. The CSS morphology and composition result in a plasmonic resonance within the near‐infrared (NIR) region of the light spectrum. Through this method, exogenous miR‐34a‐5p mimics are effectively delivered to human squamous cell carcinoma TE10 cells, leading to apoptosis induction without adverse effects on untransformed keratinocytes in vitro. The CSS nanoparticle delivery system is tested in vivo in Foxn1nu athymic nude mice with bilateral human esophageal TE10 cancer cells xenografts. These experiments reveal that this CSS nanoparticle conjugates, when systemically administered, followed by 850 nm light emitting diode irradiation at the tumor site, 6 h post‐injection, produce a significant and sustained reduction in tumor volume, exceeding 87% in less than 72 h.
Modeling broadband cloaking using 3D nano-assembled plasmonic meta-structures
The concept of “cloaking” an object is a very attractive one, especially in the visible (VIS) and near infra-red (NIR) regions of the electromagnetic spectrum, as that would reduce the visibility of an object to the eye. One possible route to achieving this goal is by leveraging the plasmonic property of metallic nanoparticles (NPs). We model and simulate light in the VIS and NIR scattered by a core of a homogeneous medium, covered by plasmonic cloak that is a spherical shell composed of gold nanoparticles (AuNPs). To consider realistic, scalable, and robust plasmonic cloaks that are comparable, or larger, in size to the wavelength, we introduce a multiscale simulation platform. This model uses the multiple scattering theory of Foldy and Lax to model interactions of light with AuNPs combined with the method of fundamental solutions to model interactions with the core. Numerical results of our simulations for the scattering cross-sections of core-shell composite indicate significant scattering suppression of up to 50% over a substantial portion of the desired spectral range (400 - 600 nm) for cores as large as 900 nm in diameter by a suitable combination of AuNP sizes and filling fractions of AuNPs in the shell.
more » « less- NSF-PAR ID:
- 10172372
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optics Express
- Volume:
- 28
- Issue:
- 15
- ISSN:
- 1094-4087; OPEXFF
- Page Range / eLocation ID:
- Article No. 22732
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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