The use of methylene blue to control the tumor oxygenation level.

Background: Hypoxia is a characteristic feature of many tumors. It promotes tumor proliferation, metastasis, and invasion and can reduce the effectiveness of many types of cancer treatment.

Objective: The aim of this study was to investigate the pharmacokinetics of methylene blue (MB) and its impact on the tumor oxygenation level at mouse Lewis lung carcinoma (LLC) model using spectroscopic methods.

Theranostic Properties of Crystalline Aluminum Phthalocyanine Nanoparticles as a Photosensitizer.

The study of phthalocyanines, known photosensitizers, for biomedical applications has been of high research interest for several decades. Of specific interest, nanophotosensitizers are crystalline aluminum phthalocyanine nanoparticles (AlPc NPs). In crystalline form, they are water-insoluble and atoxic, but upon contact with tumors, immune cells, or pathogenic microflora, they change their spectroscopic properties (acquire the ability to fluoresce and become phototoxic), which makes them upcoming agents for selective phototheranostics.

Synthesis of SrF:Yb:Er ceramic precursor powder by co-precipitation from aqueous solution with different fluorinating media: NaF, KF and NHF.

The major challenge in optical ceramic technology is the quality of the starting precursor powder for pressing, which is a key element in the optical ceramic industry. One express and helpful technique for the estimation of powder quality is the estimation of the quantum yield of up-conversion luminescence; therefore precursor powders must exhibit high values of up-conversion luminescence efficiency. Single-phase solid solutions based on strontium fluoride doped with ytterbium and erbium were synthesised by co-precipitation from aqueous solutions using sodium fluoride, potassium fluoride and ammonium fluoride as fluorinating agents.

Study of synthesis temperature effect on-NaGdF: Yb, Er upconversion luminescence efficiency and decay time using maximum entropy method.

Upconversion materials have several advantages for many applications due to their great potential in converting infrared light to visible. For practical use, it is necessary to achieve high intensity of UC luminescence, so the studies of the optimal synthesis parameters for upconversion nanoparticles are still going on. In the present work, we analyzed the synthesis temperature effect on the efficiency and luminescence decay of-NaGdYbErF(15-25 nm) upconversion nanoparticles with hexagonal crystal structure synthesized by anhydrous solvothermal technique.

Temperature Sensing in the Short-Wave Infrared Spectral Region Using Core-Shell NaGdF:Yb, Ho, Er@NaYF Nanothermometers.

The short-wave infrared region (SWIR) is promising for deep-tissue visualization and temperature sensing due to higher penetration depth and reduced scattering of radiation. However, the strong quenching of luminescence in biological media and low thermal sensitivity of nanothermometers in this region are major drawbacks that limit their practical application. Nanoparticles doped with rare-earth ions are widely used as thermal sensors operating in the SWIR region through the luminescence intensity ratio (LIR) approach.