Product Code: ICAL07_N404

Adding Functionality to Metal Nanoparticles during Femtosecond Laser Ablation in Liquids
Authors:
Jurij Jakobi, Laser Zentrum Hannover e.V.; Hannover Germany
Stephan Barcikowski, Laser Zentrum Hannover e.V.; Hannover Germany
Svea Petersen, Laser Zentrum Hannover e.V.; Hannover Germany
Anne Hahn, Laser Zentrum Hannover e.V.; Hannover Germany
Boris Chichkov, Laser Zentrum Hannover e.V.; Hannover Germany
Niko Bärsch, Laser Zentrum Hannover e.V.; Hannover Germany
Presented at ICALEO 2007

Nanoparticles are widely used in medical applications. For coupling biomolecules such as antigens and protection against corrosion, the nanoparticles have to be coated. The generation of metal nanoparticles using pulsed laser ablation in liquids is well-known, showing advantages compared to conventional methods, for example in the nearly unlimited material variety and purity of the nanoparticles. But there is still the need to add functionality to the nanoproduct for its application.

Giving several examples, this study presents the in-situ functionalisation of metal nanoparticles using surfactants and additives (polyvinylpyrrolidon, tetraethoxysilanes) that undergo physisorption and chemical reaction with laser generated copper and silver nanoparticles in different liquids. The concentration of the additive influence the particle size distribution and plasmon resonance shifts and infrared spectra allow statements on the coating efficiency and binding state. The size dispersion and nanoparticle stability is controlled using the appropriate concentration of dodecanthiole during laser ablation of gold in hexane. Moreover, silica shells can be generated to protect metal (copper and silver) nanoparticles against oxidation using in-situ coating and subsequent silica shell formation.

In summary, the in-situ functionalisation of nanoparticles during laser ablation in liquids is a route to the development of nanomaterials with added value for biomedical application.