The ability of Plasmonic nanoparticles (PNPs) to efficiently convert absorbed light energy into localized heat has made them a popular choice for photothermal medical applications. However, during the photothermal process, the diffusion of localized heat can lead to temperature management challenges. To address this issue, researchers have developed a new generation of PNPs incorporating optical phase transition materials, allowing for tunable photothermal responses without altering the geometry. This tunability is achieved through rapid changes in optical and thermal properties during phase transitions. In this study, we conducted a numerical analysis on the photothermal response of a VO2@Au smart nanoshell in both tumor and healthy liver tissue under irradiation with a nanosecond (5 ns) pulsed laser. To obtain the temperature profile, we solved a coupling problem between electromagnetism and thermodynamics. پرونده مقاله

Fluorescent carbon nanoparticles (CNPs) were prepared by nanosecond laser ablation of graphite powder in liquid. The effect of the liquid medium on photoluminescence (PL) efficiency and wavelength range were studied experimentally. Four solvents, polyethylene glycol, diethanolamine, diethylamine, and ethylenediamine were used as liquid platforms in the synthesis process. Analyzing the chemical components and optical spectral characterization of CNPs was carried out by attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy and photoluminescence (PL) spectroscopy, respectively. Moreover, the size of CNPs was estimated by using dynamic light scattering (DLS) measurements. Liquid components are determined to be a key factor affecting PL properties and nanoparticle size. The results are valuable in practical applications. پرونده مقاله

The surface-enhanced Raman scattering (SERS) method is a widely used technique for molecular structure analysis. This method relies on the enhancement of the Raman signal through the use of plasmonic nanostructures, such as gold and silver, which serve as substrate sensors. The use of pre-made sensors can effectively enhance the efficiency and cost-effectiveness of SERS. In this study, we used a fast, simple, and cost-effective method to create a suitable substrate for SERS analysis. Initially, gold colloidal nanoparticles with dimensions ranging from 50 to 80 nm were synthesized and deposited onto glass slides to create a uniform and rough substrate. To stabilize the gold nanoparticles, a sulfur compound called "1-dodecanethiol" was selected, increasing the contact angle of the sample to 45° on the glass slide. Florfenicol, one of the most common antibiotic residues in muscle foods, was selected as an analyte. Spectrum acquisitions at various points on a single slide demonstrated acceptable substrate uniformity (RSD = 8.44%). Further experiments conducted on different slides confirmed the consistency of the results (RSD = 7.90%). Finally, the reliability of the results was confirmed through spectrum acquisitions over various time intervals (RSD = 1.26%). پرونده مقاله