This article is dedicated to synthesis of aqueous solutions of nanoparticles based on rosin. Dependence of colloidal stability of rosin nanoparticles (RNP) on different factors (such as pH, solvent nature, and temperature) were investigated and discussed. Obtained RNP samples were characterized by dynamic light scattering, UV-visible absorbance spectroscopy, and scanning electron microscopy. It was found that RNP usually have size in the range 100‒200 nm with a maximal stability at neutral pH which is caused by relatively high surface charge of RNP (‒40 mV). Acidic media leads to fast precipitation of RNP, while alkali one leads to complete dissolution of the RNP due to formation of abietates (abietic acid is the main component of rosin).
Upconversion nanoparticles are good candidates for nanothermometry. The wavelength of the excitation and luminescence lie in optical window. The influence of the excitation power density on the luminescence temperature dependences is studded. Ratio of luminescence intensities linearly depends on temperature.
Phantoms are an imitation of biological tissue, which are physically modeling the propagation of light in biological tissues. They are required for different purposes, and also repeatability of results is achieved with it. So the fabrication of solid tissue phantoms containing high absorb or luminescence nanoparticles is actual problems for experimenters. The work describes fabrication processing and characteristics of solid tissue phantoms.