Laser-targeted photofabrication of gold nanoparticles inside cells

Abstract

Nanoparticle manipulation is of increasing interest, since they can report single moleculelevel measurements of the cellular environment. Until now, however, intracellular nanoparticle locations have been essentially uncontrollable. Here we show that by infusing a gold ion solution, focused laser light-induced photoreduction allows in situ fabrication of gold nanoparticles at precise locations. The resulting particles are pure gold nanocrystals, distributed throughout the laser focus at sizes ranging from 2 to 20 nm, and remain in place even after removing the gold solution. We demonstrate the spatial control by scanning a laser beam to write characters in gold inside a cell. Plasmonically enhanced molecular signals could be detected from nanoparticles, allowing their use as nano-chemical probes at targeted locations inside the cell, with intracellular molecular feedback. Such light-based control of the intracellular particle generation reaction also offers avenues for in situ plasmonic device creation in organic targets, and may eventually link optical and electron microscopy.

Towards ultrasensitive malaria diagnosis using surface enhanced Raman spectroscopy

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Synthesis of Au Nanoparticles with Benzoic Acid as Reductant and Surface Stabilizer Promoted Solely by UV Light

“…Synthesis of size-controlled and monodispersed AuNPs is therefore necessary. In particular, creation of AuNPs in “targeted position” is crucial for memory devices, photonic materials, and surface-enhanced Raman scattering (SERS) because interparticle distance and location of AuNPs strongly affect the optical properties. , A preparation method for size-controlled and monodispersed AuNPs on a targeted position by an external stimulus is therefore desired.…”

Near infrared light responsive hybrid nanoparticles for synergistic therapy

“…[19,20] However, the surface coating of gold nanoparticles and nanorods to improve their biocompatibility would weaken the therapeutic efficacy. [21,22] Polymers with photochromic groups, which was induced by light to change the architectures, have been exploited as light-sensitive polymers. [23] The wavelength of light to trigger the reversible photoisomerization or irreversible photocleavage of light sensitive polymers was located in the region of UV or visible light.…”