Light-Induced Condensation of Biofunctional Molecules around Targeted Living Cells to Accelerate Cytosolic Delivery

Abstract

The light-induced force and convection can be enhanced by the collective effect of electrons (superradiance and red shift) in high-density metallic nanoparticles, leading to macroscopic assembly of target molecules. We here demonstrate application of the light-induced assembly for drug delivery system with enhancement of cell membrane accumulation and penetration of biofunctional molecules including cell-penetrating peptides (CPPs) with superradiancemediated photothermal convection. For induction of photothermal assembly around targeted living cells in cell culture medium, infrared continuous-wave laser light was focused onto high-density gold-particle-bound glass bottom dishes exhibiting plasmonic superradiance or thin gold-film-coated glass bottom dishes. In this system, the biofunctional molecules can be concentrated around the targeted living cells and internalized into them only by 100 s laser irradiation. Using this simple approach, we successfully achieved enhanced cytosolic release of the CPPs and apoptosis induction using a pro-apoptotic domain with a very low peptide concentration (nM level) by light-induced condensation.

Highly Efficient Three-dimensional Optical Condensation of Microbes Using a Gold-coated Optical Fibre Module

“…Here, thermal convection transports dispersoids toward the bubble, assembling them between the bubble and the substrate. This phenomenon, termed optical condensation, is utilized for assembling nano-micro particles and bacterial clusters [22][23][24] . Optical condensation is particularly anticipated to be valuable in biological analysis, which is both timeconsuming and costly.…”

Ultra-low intensity light pulses for large cargo delivery into hard-to-transfect cells using an rGO mixed PDMS microtip device

“…33 Similar to photoporation, light exposure induced force and convection was employed to achieve intracellular delivery; however, the exposure time is longer (∼100 s). 34 Advancements in nanotechnology helped to provide various nanoparticles (NPs) with plasmonic or photothermal properties to achieve photoporation with lower laser energy and shorter exposure time, thereby reducing cell damage. [34][35][36][37][38][39][40] Over the years, NP-mediated photoporation has evolved as a universal non-viral intracellular delivery tool that combines flexibility, safety, and efficiency.…”

“…34 Advancements in nanotechnology helped to provide various nanoparticles (NPs) with plasmonic or photothermal properties to achieve photoporation with lower laser energy and shorter exposure time, thereby reducing cell damage. [34][35][36][37][38][39][40] Over the years, NP-mediated photoporation has evolved as a universal non-viral intracellular delivery tool that combines flexibility, safety, and efficiency. 41 Various photothermal NPs, including those contained noble metals (gold and silver), iron oxide, carbon-based NPs (carbon nanotubes, graphene, and polymer), and quantum dots, have been employed to achieve NP-mediated photoporation.…”

High-throughput light-induced immunoassay with milliwatt-level laser under one-minute optical antibody-coating on nanoparticle-imprinted substrate

“…Thus, the synergistic effects of both light-induced forces due to electromagnetic interaction and light-induced convection due to thermodynamic interaction were used for highly efficient optical condensation of various biological nanomaterials, and also the pressure-driven flow mediates optical condensation 24,27,28 . Such optical condensation can be used for high-density trapping of micron-order particles and bacteria 24,29 and cellpenetrating biofunctional molecules 30 using the region between the bubble and the substrate, generated through local heating with a focused laser, as an aggregation site. Honeycomb substrates and bowl-shaped substrates (BPS) with micro-scale periodic multiple pores, which enable high concentration while suppressing thermal transfer to the trapped bacteria, have been developed 31,32 ; the principle of low-damage optical condensation by bubblemimetic substrates has been reported 33 .…”