Search

We have established numerically the physical pattern and conditions for formation of nanosized bubbles in aqueous medium around biocompatible plasmonic nanoparticles (NPs) selectively bound to the membrane of the malignant cells by means of DNA-aptamers under the action of picosecond laser radiation. The results obtained are based on the finite volume method and hydrodynamic models underlying the ANSYS Fluent package with extended capabilities. We have found the main features and previously unknown dominant factors of the damage effect on the cell membrane at the moment of the bubble nucleation around the plasmonic NPs of different types taking into account the influence of the closely located membrane. Information on the kinetics of spatial distribution of pressure, temperature and the relative proportion of vapor in the ‘nanoparticle-membrane-medium’ system have been obtained. The attention is drawn to the advantages of using biocompatible, perfectly absorbing core–shell plasmonic NPs for anti-tumor therapy characterized by an increased mechanical effect on malignant cell membranes at lower laser radiation intensity and the spectral position of their plasmon resonance (λ = 700 nm) in the hemoglobin transparency range. This ensures penetration of laser radiation deep into tissues. The paper is provided with an extensive review of key publications and the state-of-art in this area.

We numerically investigate the conditions for the laser-induced formation of nanobubbles in aqueous medium around plasmonic nanoparticles (NPs) bound to the malignant cell membranes that is considered as the method of their irreversible damage. We proposed employing the versatile and accessible simulation software as a research tool based on the finite volume method underlying the ANSYS Fluent package and supplemented with our user-defined functions that adapt it to solution of the stated problems. This adaptation allows to verify the model using experimental data for the same conditions. We determined the conditions for the pressure growth on the cell membrane at the initial moment of bubble formation significantly exceeding the threshold of irreversible damage. The model can be used for investigation of hydrodynamic effects accompanying irradiation of plasmonic NPs using both different types of pulsed lasers and ideally absorbing NPs with resonance in the hemoglobin spectral transparency range, as well as to uncover previously unknown effects. They include the conditions for localization of a damaging factor non-affecting the normal cells, the conditions for generation of ultrahigh pressure pulse that enables to damage the cell membrane and precedes formation of thin vapor shell around NPs, which, unlike large bubbles, requires registration using highly sensitive experimental measurements. An extensive overview of key publications summarizing the state-of-art in this area is presented.