Laser-Activated Self-Assembled Thermoplasmonic Nanocavity Substrates for Intracellular Delivery

Abstract

Intracellular delivery is crucial for cellular engineering and the development of therapeutics. Laser-activated thermoplasmonic nanostructured surfaces are a promising platform for high-efficiency, high-viability, highthroughput intracellular delivery. Their fabrication, however, typically involves complicated nanofabrication techniques, limiting the approach's applicability. Here, colloidal self-assembly and templating are used to fabricate large arrays of thermoplasmonic nanocavities simply and cost-effectively. These laseractivated substrates are used to deliver membrane-impermeable dye into cells at an efficiency of 78% and throughput of 30 000 cells min −1 while maintaining 87% cell viability. Proof-of-concept data show delivery of large cargoes ranging from 0.6 to 2000 kDa to cells without compromising viability.

Vapor nanobubble-mediated photoporation constitutes a versatile intracellular delivery technology

“…Madrid et al fabricated a silica nanocavity substrate coated with a thin titanium film through a self-assembly process that allows for fairly easy manufacturing of the substrate (Figure 4B) [49]. Upon 11 ns 1064 nm pulsed laser irradiation, extreme and rapid heating followed by the generation of cavitation bubbles was reported, which led to intracellular delivery of calcein (~78% positive cells) at a throughput of 30 000 cells/min and a cell viability of ~87%, as determined by microscopy analysis of Calcein AM live-cell staining.…”

“…Optimal laser fluence, however, was a factor 5 lower (~11 mJ/cm²), which may be attributed to the generation of multiple hotspots at the nanodisk edges rather than a single one at the pyramid tip. Reproduced with permission from [49]. Copyright 2018 American Chemical Society.…”

Intracellular Labeling with Extrinsic Probes: Delivery Strategies and Applications

“…A similar substrate was fabricated by Madrid et al who achieved 78% calcein green positive cells with 87% cell viability (Figure 8b). [ 110 ] Lyu et al developed a flat substrate with an immobilized gold nanoparticle layer suitable for irradiation by an 808 nm CW laser (Figure 8c). [ 111 ] Tetramethylrhodamine isothiocyanate (TRITC)‐labeled dextran (4.4 kDa) was delivered into cells with high viability.…”

“…Reproduced with permission. [ 110 ] Copyright 2018, American Chemical Society. c) Schematic illustration of macromolecular delivery into living cells grown on gold nanoparticle layer surfaces upon laser irradiation.…”

Delivery of Foreign Materials into Adherent Cells by Gold Nanoparticle-Mediated Photoporation

“…This method resulted in a delivery efficiency of 95% for 0.623-kDa-sized membrane-impermeable fluorescent dye while maintaining 98% cell viability. In a recent study [ 26 ], a new plasmonic substrate, a self-assembled thermoplasmonic titanium nanocavity, was designed on which adherent HeLa cells were incubated. This platform was used to deliver calcein green (0.623 kDa) into cells at an efficiency of 78% and viability of 87%.…”