Green Synthesis of Hyperbranched Polyglycerol at Room Temperature.

In this work we report on a new method for the cationic polymerization of glycidol by citric acid at ambient and solvent free conditions. In this polymerization, citric acid is a proton donor and is able to incorporate in the structure of polyglycerol by reaction with the activated monomer. The molecular weight and degree of branching of the synthesized polymers are affected by the glycidol/citric acid molar ratios and reaction temperature. Due to the citric acid core of the hyperbranched polyglycerols, they are able to break down into the smaller segments at neutral or acidic conditions. Apart from citric acid, glycidol, and water, other reagents or organic solvents have not been used in the synthetic and purification processes. Taking advantage of the green synthesis and ability to cleave under physiological conditions, in addition to the intrinsic biocompatibility of polyglycerol, the synthesized polymers are promising candidates for future biomedical applications.

Broadband and Low-Loss Plasmonic Light Trapping in Dye-Sensitized Solar Cells Using Micrometer-Scale Rodlike and Spherical Core-Shell Plasmonic Particles.

Dielectric scattering particles have widely been used as embedded scattering elements in dye-sensitized solar cells (DSCs) to improve the optical absorption of the device. Here we systematically study rodlike and spherical core-shell silica@Ag particles as more effective alternatives to the dielectric scattering particles. The wavelength-scale silica@Ag particles with sufficiently thin Ag shell support hybrid plasmonic-photonic resonance modes that have low parasitic absorption losses and a broadband optical response. Both of these features lead to their successful deployment in light trapping in high-efficiency DSCs. Optimized rodlike silica@Ag@silica particles improve the power conversion efficiency of a DSC from 6.33 to 8.91%. The dimension, surface morphology, and concentration of these particles are optimized to achieve maximal efficiency enhancement. The rodlike silica particles are prepared in a simple one-pot synthesis process and then are coated with Ag in a liquid-phase deposition process by reducing an Ag salt. The aspect ratio of silica rods is tuned by adjusting the temperature and duration of the growth process, whereas the morphology of Ag shell is tailored by controlling the reduction rate of Ag salt, where slower reduction in a polyol process gives a smoother Ag shell. Using optical calculations, the superior performance of the plasmonic core-shell particles is related to the large number of hybrid photonic-plasmonic resonance modes that they support.

Polyamidoamine and polyglycerol; their linear, dendritic and linear-dendritic architectures as anticancer drug delivery systems.

Despite extensive investigations in the field of cancer diagnosis and therapy in recent decades, cancer is still the major cause of morbidity and mortality all over the world. Recently, with the advancement of nanotechnology, the design and preparation of efficient nano-sized structures with the potential for diagnosis and treatment of cancer have been proposed. Among the different types of nano-sized materials, biocompatible polymers seem to be innovative tools with huge potential for cancer treatment. Advances in polymer chemistry and the application of various organic reactions have enabled the design and tailoring of multifunctional polymeric platforms with controllable architectures, with the ability to carry anticancer drugs, labelling probes and targeting agents simultaneously. This review covers the latest advances in the conjugation of the most studied chemotherapeutics (such as doxorubicin, paclitaxel, methotrexate, fluorouracil and cisplatin) to common dendritic polymers, including polyamidoamine dendrimers and hyperbranched polyglycerols (PGs) and their linear analogues, producing fatal weapons against tumors, with a focus on their cytotoxicity, biodistribution and biodegradability.

Preparation and quality control of the [sm]-samarium maltolate complex as a lanthanide mobilization product in rats.

Development of lanthanide detoxification agents and protocols is of great importance in management of overdoses. Due to safety of maltol as a detoxifying agent in metal overloads, it can be used as a lanthanide detoxifying agent. In order to demonstrate the biodistribution of final complex, [(153)Sm]-samarium maltolate was prepared using Sm-153 chloride (radiochemical purity >99.9%; ITLC and specific activity). The stability of the labeled compound was determined in the final solution up to 24h as well as the partition coefficient. Biodistribution studies of Sm-153 chloride, [(153)Sm]-samarium maltolate were carried out in wild-type rats comparing the critical organ uptakes. Comparative study for Sm(3+) cation and the labeled compound was conducted up to 48 h, demonstrating a more rapid wash out for the labeled compound. The effective and biological half lives of 2.3 h and 2.46h were calculated for the complex. The data suggest the detoxification property of maltol formulation for lanthanide overdoses.

2-Amino-pyridinium diphenyl-phosphinate monohydrate.

In the crystal of the title hydrated salt, C(5)H(7)N(2) (+)·C(12)H(10)O(2)P(-)·H(2)O, the cations, anions and water mol-ecules connected by N-H⋯O and O-H⋯O hydrogen bonds into a layer along the bc plane; the phenyl rings protrude into the space between the layers. The dihedral angle between rings of anion is 86.1 (1)°.

Monoclinic modification of 1,2-bis-(diphenyl-seleno-phosphino-yl)ethane.

The complete mol-ecule of the title compound, C(26)H(24)P(2)Se(2), is generated by crystallographic 2-fold symmetry, with the rotation axis bisecting the central C-C bond. The dihedral angle between the terminal aromatic rings is 74.1 (1)°.