Cell perforation mediated by plasmonic bubbles generated by a single near infrared femtosecond laser pulse

We report on transient membrane perforation of living cancer cells using plasmonic gold nanoparticles (AuNPs) enhanced single near infrared (NIR) femtosecond (fs) laser pulse. Under optimized laser energy fluence, single pulse treatment (τ = 45 fs, λ = 800 nm) resulted in 77% cell perforation efficiency and 90% cell viability. Using dark field and ultrafast imaging, we demonstrated that the generation of submicron bubbles around the AuNPs is the necessary condition for the cell membrane perforation. AuNP clustering increased drastically the bubble generation efficiency, thus enabling an effective laser treatment using low energy dose in the NIR optical therapeutical window

Cell perforation mediated by plasmonic bubbles generated by a single near infrared femtosecond laser pulse

We report on transient membrane perforation of living cancer cells using plasmonic gold nanoparticles (AuNPs) enhanced single near infrared (NIR) femtosecond (fs) laser pulse. Under optimized laser energy fluence, single pulse treatment (τ = 45 fs, λ = 800 nm) resulted in 77% cell perforation efficiency and 90% cell viability. Using dark field and ultrafast imaging, we demonstrated that the generation of submicron bubbles around the AuNPs is the necessary condition for the cell membrane perforation. AuNP clustering increased drastically the bubble generation efficiency, thus enabling an effective laser treatment using low energy dose in the NIR optical therapeutical window

Polymer/carbon nanotube composite patterns via laser induced forward transfer

Direct and high spatial resolution printing of polymer/carbon nanotube (CNT) composite layers has been demonstrated by means of laser induced forward transfer (LIFT). Laser irradiation of composite target materials, such as poly(acrylic acid)/CNT and polyvinylpyrrolidone/CNT, enabled dry deposition of well resolved composite pixels onto glass substrates. The dispersion of the CNT into the deposited composite pixels was investigated by transmission electron microscopy. The LIFT technique was also employed for the accurate deposition of polymer/CNT composite pixels onto aluminum microelectrodes for the fabrication of chemical sensors based on polymer/CNT compounds. © 2010 American Institute of Physics

A time-resolved shadowgraphic study of laser transfer of silver nanoparticle ink

Spring Meeting of the European-Materials-Research-Society (E-MRS) / Symposium N / Symposium O / Symposium V on Laser Materials Processing for Micro and Nano Applications, Strasbourg, FRANCE, MAY 14-18, 2012International audienceThe dynamics of liquid phase laser induced forward transfer (LIFT) of silver nanoparticle (NP) ink (particle size 30-50 nm) was investigated by time-resolved shadowgraphic imaging. LIFT was carried out by a KrF excimer laser (248 nm, 35 ns) using two donor substrate configurations: (a) a wet silver NP ink layer spread on a quartz substrate and (b) a wet silver NP ink layer spread on a quartz substrate covered by a 40nm thick titanium layer. This comparative study revealed a completely different ejection mechanism for the two different donor configurations. The use of the titanium dynamic release layer (DRL) resulted in a highly directional and low velocity ejection of the material for a wide range of laser fluences. On the other hand, LIFT of silver NP ink without using the titanium DRL provoked supersonic velocity ejection and shock wave generation for laser fluences even slightly above the ejection threshold. The velocity of the ejected material (13-240 m/s) in the case of titanium DRL assisted LIFT was significantly lower than the one observed without using DRL (106-830 m/s). The use of the titanium DRL layer expanded, significantly, the processing window for directional and low velocity ejection of the silver NP ink. (C) 2012 Elsevier B. V. All rights reserved