An Easily Accessible NIR-Absorbing Tetraimide Dye and its Biotherapeutics Based Photothermal and Photodynamic Therapy

Organic π-systems with strong absorption in the near-infrared (NIR) region are promising candidates for photothermal therapy (PTT) and photodynamic therapy (PDT). However, the synthesis of NIR π-systems involves several steps and many of them display poor photothermal conversion efficiency (PTCE). Here we present the synthesis of a tetraimide-based donor-acceptor NIR π-system, 2EHex-B having absorbance in the range of 350–900 nm. Importantly, 2EHex-B is synthesized in two steps with a 70 % high yield. Moreover, 2EHex-B shows excellent PTCE up to 50 % and good biocompatibility when encapsulated in liposomes. The liposome coated 2EHex-B , ( L-2EHex-B) showed good thermal stability and efficiently kills cancer cells via PTT. Additionally, L-2EHex-B shows good reactive singlet oxygen generation ability when irradiated with a 750 nm laser. 3D cell culture model - multicellular spheroids test was performed to evaluate the efficiency of PTT. The spheroids treated with L-2EHex-B after NIR light irradiation showed increased cell death from the core of the tumor toward the periphery. The easy access to 2EHex-B makes it a potential candidate for minimally invasive cancer treatment.     

Thermal diffusivity of lead titanate/polyvinylidene fluoride-trifluoroethylene nanocomposites by the mirage method

Thermal diffusivity D of lead titanate/polyvinylidene fluoride-trifluoroethylene {PT/P(VDF-TrFE)} nanocomposites has been measured by the skimming configuration of the mirage method. Diffusivity values are calculated by measuring the phase variation of the probe beam deflection signal upon changing both the vertical and horizontal probe beam offset values at different modulation frequencies of the pump beam. The thermal diffusivity of the nanocomposites is found to depend on the volume fraction of the ceramic in the composites. The composites with higher volume fraction of ceramic have higher thermal diffusivity and conductivity. Different models were used to predict the thermal conductivity (k) of composites and the measured values agree quite well with the Looyenga model.     

Synthesis of Silver Nanoparticles Using Syzygium malaccense Fruit Extract and Evaluation of Their Catalytic Activity and Antibacterial Properties

Journal of Inorganic and Organometallic Polymers and Materials - In this study, green synthesis of silver nanoparticles, an aqueous Syzygium malaccense fruit extract, was employed...