Enhancement of extracellular molecule uptake in plasmonic laser perforation

Abstract

The use of laser induced surface plasmons on metal nanoparticles has proven to be an excellent tool for the delivery of molecules like siRNA and DNA into cells. However, a detailed understanding of the basic mechanisms of molecular uptake and the influence of parameters like biological environment is missing. In this study we analyzed the uptake of fluorescent dextrans with sizes from 10 to 2000 kDa, which resembles a wide range of biologically relevant molecules in size using a 532 nm picosecond laser system and 200 nm gold nanoparticles. Our results show a strong uptake-dependence on cell medium or buffer, but no dominant dependence on osmotic conditions. The relation between pulse energy and number of pulses for a given perforation efficiency revealed that multiphoton ionization of water might contribute to perforation. Moreover, a seven-fold uptake-enhancement could be reached with optimized parameters, providing a very promising basis for further studies and applications.

Biodegradable microsphere-mediated cell perforation in microfluidic channel using femtosecond laser

“…Another promising method is the use of gold nanoparticles, which has been called gold nanoparticles-mediated (GNOME) laser transfection. [11][12][13][14][15] Boulais et al 15,16 stated that the generation of shock waves in water by the interaction of gold nanoparticles and ultrashort laser pulses is attributable to plasma expansion mediated by plasmonic near-field instead for rapid temperature increase. The scheme for GNOME laser transfection shows applications for cell manipulation reported in the latest publications.…”

Laser-assisted photoporation: fundamentals, technological advances and applications

“…Heisterkamp group performed photoporation experiments under similar conditions (120 fs pulse, λ = 800 nm) using 200 nm AuNPs. Also Heinemann and Kalies claimed that multiphoton ionization of water was the main photoporation mechanism in their experiments, even though they used substantially longer 850 ps laser pulses (wavelength at 532 nm) in combination with 200 nm AuNPs [73,138].…”

Immobilization of gold nanoparticles on cell culture surfaces for safe and enhanced gold nanoparticle-mediated laser transfection

“…The delivery of siRNA, Morpholinos, and dextrans of sizes up to 2000 kDa was demonstrated using this setup. 1,4,5 For this purpose, 80 to 200-nm gold nanoparticles were analyzed. Baumgart et al 2 used femtosecond laser pulses to deliver DNA to cells by the irradiation of 100-nm gold nanoparticles.…”

“…Furthermore, the viability is tested with the viability indicator QBlue which is based on the reduction of resorufin in metabolically active cells 1 h after laser treatment. Heinemann et al 1,4,5 also give a more detailed protocol.…”

“…1(b). 1,4,5 We also investigated whether the procedure in conjunction with laser perforation influences the long-term viability of the cells (see Fig. 3).…”