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Photothermal therapy (PTT) has attracted increasing interest as a complementary method to be used alongside conventional therapies. Despite a great number of studies in this field, only a few have explored how temperatures affect the outcome of the PTT at nanoscale. In this work, we study the necrosis/apoptosis process of cancerous cells that occurs during PTT, using a combination of local laser heating and nanoscale fluorescence thermometry techniques. The temperature distribution within a whole cell was evaluated using fluorescence lifetime imaging microscopy during laser-induced hyperthermia. For this, gold nanorods were utilized as nanoheaters. The local near-infrared laser illumination produces a temperature gradient across the cells, which is precisely measured by nanoscale thermometry. This allows one to optimize the PTT conditions by varying concentration of gold nanorods associated with cells and laser power density. During the PTT procedure, such an approach enables an accurate determination of the percentages of apoptotic and necrotic cells using 2D and 3D models. According to the performed cell experiments, the influence of temperature increase during the PTT on cell death mechanisms has been verified and determined. Our investigations can improve the understanding of the PTT mechanisms and increase its therapeutic efficiency while avoiding any side effects.

To prevent implant-associated infections, surface modifications need to be developed that prevent bacterial colonisation and biofilm formation. In the present study, titanium surfaces were processed by nanosecond-pulsed laser ablation to generate a variety of different structures (anatase, rutile, Osteon, as well as Osteon additionally coated with silver and clove nanoparticles). Analysis of adhesion and biofilm formation of the oral pioneer bacterium Streptococcus oralis could demonstrate antibacterial properties of anatase surfaces. For clinical translation, the effect should be enhanced by further adaption and combined with the osseointegrative Osteon structure

The development of systems capable of efficiently eliminating organic dyes from wastewater is crucial for the environment. In this context, TiO2-based photocatalytic systems are of particular interest. However, the development of eco-friendly and single-step methods for the fabrication of such systems remains a challenge to their practical use. Here, we demonstrate a fabrication approach for a catalytic system composed of TiO2 nanocoating created on the surface of a bulk titanium plate by exposure to a nanosecond laser. The exposure conditions affect the relief and phase composition of the nanocoating, as revealed by a combination of scanning electron microscopy (SEM), contact profilometry, Raman, High-resolution X-ray photoelectron spectroscopy (HR XPS), and grazing incidence X-ray diffraction (GIXRD) methods. Using the GIXRD method, we establish that nanocoatings consist of a mixture of anatase and rutile grains with sizes of 22.7–24.4 and 29.8–32.2 nm, respectively. HR XPS analysis demonstrates that changes in the number of pulses per spot modify the anatase surface content from 40.6 to 70.4%. The samples with a higher anatase content exhibit up to 6.3 times higher catalytic activity, which is confirmed by methylene blue degradation when exposed to UV light and can be related to the synergistic effect of the anatase–rutile heterojunction. The reusability of the samples is supported by repeated degradation experiments. The photocatalytic activity of the obtained TiO2 nanocoatings is improved by Au nanoparticles deposited on their surface by magnetron sputtering. The proposed approach lays the foundation for the application of nanosecond laser-assisted technologies in the eco-friendly fabrication of catalytic systems. [ABSTRACT FROM AUTHOR]