Delivery of upconversion microparticles [Y2O3:Yb, Er] and quantum dots (CuInS2/ZnS coated with PEG-based amphiphilic polymer) into rat skin using the fractional laser microablation has been studied in vivo. Luminescence spectroscopy, optical coherence tomography, confocal microscopy, and histochemical analysis were used for visualization of nanoparticles in microchannels. Results have shown that the upconversion microparticles are detected more efficiently in comparison with the quantum dots. The fluorescence intensity of the inserted upconversion microparticles is higher, when the Omnipaque™ was applied as a skin optical clearing agent. The fluorescent images of upconversion nanoparticle distribution indicate the advantage of particle delivery into skin by ultrasound.
Internal temperature of biological tissues was measured in real-time mode under close-to-in-vivo conditions. Research technique is based on the comparison of the temperature inside the biological object and changes in the fluorescence spectra of temperature-sensitive fluorescent semiconductor ZnCdS nanoparticles introduced into muscle tissue. The temperature dependence of the ratio of maximum fluorescence intensities of the nanoparticles and the biological tissue was approximately linear.
The wide application of optical methods in the areas of diagnostics, therapy and surgery of modern medicine has
stimulated the investigation of optical properties of various biological tissues. Numerous investigations related to
determination of tissue optical properties are available; however, the optical properties of many tissues have not been
studied in a wide wavelength range. In this work the optical properties of parietal peritoneum in the wavelength range
350-2500 nm were measured. Measurement of the diffuse reflectance, total and collimated transmittance were performed
using LAMBDA 950 (Perkin Elmer, USA) spectrophotometer with an integrating sphere, and values of absorption and
scattering coefficients, and the scattering anisotropy factor were calculated by inverse Monte Carlo Method.