Nonlinear Optical Properties of Novel Metallophthalocyanines

Journal of Applied Spectroscopy - Detailed measurements of nonlinear optical properties and optical limiting for four phthalocyanine (Pc) derivatives (PcCo, PcCu, PcMn, and PcSi) are reported. The...     

Synthesis of gold nanorod/single-wall carbon nanotube heterojunctions directly on surfaces

This contribution describes the synthesis of gold nanorod (Au NR)/single-wall carbon nanotube (SWCNT) heterojunctions assembled directly on Si/SiOx substrates. SWCNTs are attached to amine-functionalized Si/SiOx substrates, and Au monolayer-protected clusters (MPCs) are adsorbed to the surface of SWCNTs through hydrophobic interactions. Seed-mediated reduction of HAuCl4 with ascorbic acid in the presence of cetyltrimethylammonium bromide (CTAB) onto the Au MPCs leads to the growth of larger Au nanostructures directly on the SWCNTs. Au NRs account for 19% of the nanostructures, some of which are attached directly to the sidewall and some at the ends of the SWCNTs. Raman spectroscopic measurements of SWCNTs before and after growth of the Au nanostructures reveal that the presence of Au leads to an approximately 50-fold enhancement of the Raman scattering signal. Combining 1D nanostructures of different materials (Au and carbon in this example) is of fundamental interest and may find use in nanoelectronics, chemical sensing, electrochemical, and spectroscopy applications.     

Preparation and biodistribution of [67Ga]-DTPA-rituximab in normal rats

Rituximab was successively labeled with [⁶⁷Ga]-gallium chloride after residulation with freshly prepared cyclic DTPA-dianhydride. The best results of the conjugation were obtained by the addition of 1 ml of a rituximab pharmaceutical solution (5 mg/ml, in phosphate buffer, pH 8) to a glass tube pre-coated with DTPA-dianhydride (0.01 mg) at 25 °C with continuous mild stirring for 30 minutes. Radio thin-layer chromatography showed an overall radiochemical purity of 96–99% at optimized conditions (specific activity = 300–500 MBq/mg, labeling efficiency 77%). The final isotonic ⁶⁷Ga-DTPA-rituximab complex was checked by gel electrophoresis for radiolysis control. Radio-TLC was performed to ensure the formation of only one species, followed by filtration through a 0.22 μm filter. Preliminary in vivo studies in normal rat model was performed to determine the biodistribution of the radioimmunoconjugate up to 6 hours.     

Preparation, nano purification, quality control and labeling optimization of [64Cu]-5,10,15,20-tetrakis (penta fluoro phenyl) porphyrin complex as a possible imaging agent

Cu-64 was produced via the ⁶⁸Zn (p,αn)⁶⁴Cu nuclear reaction (≈200 mCi, >95 % chemical yield at 180 μA for 1.1 h irradiation, (radionuclidic purity >96 %, copper-67 as impurity) followed by purification with amino functionalized nano magnetic oxide, Fe₃O₄ aiming to remove trace amount of heavy metal ions from aqueous media due to achieve ultra pure [⁶⁴Cu] CuCl₂ for labeling step. [⁶⁴Cu] labeled 5,10,15,20-tetrakis(penta fluoro phenyl) porphyrin ([⁶⁴Cu]-TFPP) was prepared using freshly prepared [⁶⁴Cu] CuCl₂ (Cu-64; T _1/2 = 12.7 h) and 5,10,15,20-tetrakis(penta fluoro phenyl)porphyrin (H₂TFPP) for 60 min at 100 °C under reflux condition (radiochemical purity: >97 % ITLC, >98 % HPLC, specific activity: 14–16 GBq/mmol). Stability of the complex was checked in final formulation and human serum for 24 h. The partition coefficient was calculated for the compound (log P = 0.73). The biodistribution of the labeled compound in vital organs of wild-type rats was studied using scarification studies and PET imaging up in 2 and 4 h after injection. A detailed comparative pharmacokinetic study performed for ⁶⁴Cu cation and [⁶⁴Cu]-TFPP. The complex is mostly washed out from the circulation through kidneys and liver and can be an interesting tumor imaging/targeting agent due to high specific uptake and rapid excretion through the urinary tract.     

Radiosynthesis and biological evaluation of 166Ho labeled methoxylated porphyrins as possible therapeutic agents

¹⁶⁶Ho labeled 5,10,15,20-tetrakis(3,4-dimethoxyphenyl) porphyrin, and 5,10,15,20-tetrakis(3,4,5-trimethoxyphenyl) porphyrin ([¹⁶⁶Ho]–TDMPP and [¹⁶⁶Ho]–TTMPP respectively) were prepared with acceptable radiochemical purity and specific activities. Stability and partition coefficient of the complexes were determined in the final formulations and biodistribution studies in mouse demonstrated high accumulation of [¹⁶⁶Ho]–TDMPP in the lung and liver and less excretion through the kidney. while [¹⁶⁶Ho]–TTMPP was mostly excreted into intestines and kidneys while lungs were a minor accumulation site. In contrast to other reported radiolanthanide labeled porphyrins these two complexes showed less liver accumulation. Further investigation of their potential therapeutic properties is of interest.     

Uranium concentration in blood samples of Southern Iraqi leukemia patients using CR-39 track detector

The simple and effective technique of fission track etch has been applied to determine trace concentration of uranium in human blood samples taken from two groups of male and female participants: leukemia patients and healthy subjects group. The blood samples of leukemia patients and healthy subjects were collected from three key southern governorates namely, Basrah, Muthanna and Dhi-Qar. These governorates were the centers of intensive military activities during the 1991 and 2003 Gulf wars, and the discarded weapons are still lying around in these regions. CR-39 track detector was used for registration of induced fission tracks. The results show that the highest recorded uranium concentration in the blood samples of leukemia patients was 4.71 ppb (female, 45 years old, from Basrah) and the minimum concentration was 1.91 ppb (male, 3 years old, from Muthanna). For healthy group, the maximum uranium concentration was 2.15 ppb (female, 55 years old, from Basrah) and the minimum concentration was 0.86 ppb (male, 5 years old, from Dhi-Qar). It has been found that the uranium concentrations in human blood samples of leukemia patients are higher than those of the healthy group. These uranium concentrations in the leukemia patients group were significantly different (P < 0.001) from those in the healthy group.     

Injection locked multi-section gain-coupled dual mode DFB laser for terahertz generation

A dual mode multi-section gain-coupled distributed feedback laser with tunable mode spacing is subharmonically injection locked at 0.315 THz. The injected signal consists of an optical comb with harmonics 35 GHz apart and a bandwidth of approximately 1.9 THz. The optical comb is a result of strong four-wave mixing in a highly-nonlinear dispersion-shifted fiber. In order to observe locking of the multi-section laser, the output is optically downconverted to RF frequencies using the same optical comb. The locked multi-section DFB laser is a coherent and tunable optical source suitable for continuous-wave terahertz generation systems.