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A novel mu-nitrido iron phthalocyanine-iron porphyrin complex has been synthesised and characterised, preliminary DFT calculations have been performed in order to elucidate its UV-vis spectrum.

Phthalocyanines based-dyes represent attractive alternatives to the expensive and polluting pyridyl based Ru complexes because of their photochemical and thermal stability, they do show in fact intense absorption in the UV/blue (Soret band) and the red/near IR (Q band) spectral regions and appear very promising as sensitizer dyes for DSSC. In this contribution we review the state of the art and the recent progress in the application of these materials as dyes for DSSC and present three new dyes which are bridged derivatives of Iron phthalocyanine. Synthesis, optical properties, electrochemical characterization and device performances are discussed with regard to the different substitution degree of the macrocycle.

Lipocalin-2 (LCN2) is a member of the lipocalin family, small secreted proteins functioning as modulators of many different physiological processes including cell differentiation, proliferation and apoptosis. LCN2 expression is also up-regulated in several pathological conditions, including inflammation and cancer. LCN2 synthesis has been described in epithelia, bone and cells of the immune system. Despite its wide expression the role of LCN2 remains to be fully elucidated. To better understand the role of this lipocalin in the bone/bone marrow system we generated transgenic mice over-expressing LCN2 specifically in bone under the control of a type I collagen promoter. In the bone marrow of these transgenic mice we observed an increased expression of SDF-1 that correlated with an increased number of CD34+/CXCR4+ (SDF-1 receptor) cells. To some extent, this appeared due to an enhanced cell proliferation rate. The higher level of the factor synthesis and the increased number of cells expressing its receptor was maintained during animal aging. Our results show that LCN2 could play a role in determining the number of CD34+/CXCR4+ precursor cells in the bone marrow thus contributing to the control of the bone marrow microenvironment.

We report on the use of thermal annealing to improve the behavior of NO2 gas-sensing ruthenium phthalocyanine films at high temperatures. The approach used, based on the study of the effect of temperature on the film morphology, makes use of in situ energy dispersive X-ray reflectometry and atomic force microscopy. The results show that the morphological changes, induced by high working temperatures, strongly affect the material sensing ability. Furthermore, we demonstrate that the film morphology may be stabilized by thermal annealing treatments, thus enhancing the sensor performances in terms of response times and the capability to work at high temperatures.

The usage of a modified Z-scan setup for the study of optical nonlinearities of bisphthalocyanines is discussed. The setup leads to the selection of the pure electronic nonlinear optical response purged from other possible contributions such as molecular reorientation or thermal effects. The described experimental method is based on the capability to extract the instantaneous nonlinear response of the sample, by monitoring and managing cumulative effects and taking full advantage of the large number of probing laser pulses. This kind of approach has been applied on some sandwich-type metal bis-phthalocyanines confirming its potential for an in-depth analysis of the nonlinear response of such molecules. First results on titanium, niobium and tin bis-phthalocyanines provide information on the role of the conjugation length in their nonlinear optical response.

Multipotent mesenchymal stromal cells isolated from bone marrow and other sites are currently being studied to determine their potential role in the pathogenesis and/or management of autoimmune diseases. In vitro studies have shown that they exhibit a dose-dependent antiproliferative effect on T and B lymphocytes, dendritic cells, natural killer cells and various B cell tumour lines - an effect that is both cell contact and soluble factor dependent. Animal models of autoimmune disease treated with multipotent mesenchymal stromal cells have mostly exhibited a positive clinical response, as have a limited number of patients suffering from acute graft versus host disease. This review summarizes the findings of a 1-day meeting devoted to the subject with the aim of coordinating efforts. © 2007 BioMed Central Ltd.

A systematic time-resolved energy dispersive x-ray reflectometry study was performed in situ on Ruthenium Phthalocyanine thin fims to estimate the morphological detection limits of this material as NO2 transducer and the influence of the gas concentration on the gas-film interaction mechanisms. The work validates the use of this unconventional method—based on the observation of the morphological parameters change—for evaluating the response of novel sensing materials in alternative to more standard procedures. Indeed, the morphological monitoring is shown to be sensitive to the gas concentration in a range comparable to the usual electroresistive measurements. Moreover, while the latter is only able to give the information on whether the gas is interacting with the sensor, the former is also able to discriminate among interaction processes of a different nature (in the present case the interaction limited to the film surface and the one involving the material bulk).

An STM-UHV study of the deposition of titanium bis-phthalocyanine under high vacuum (UHV) conditions on two different substrates such as GaAs (100)-beta 2-(2X4)and highly oriented pyrolytic graphite (HOPG) has been carried out. An STM spectroscopic analysis on the local density of states has also been performed .In the case of a GaAs as substrate , the STM images show that the molecules align themselves preferentially along the dimer rows , typical of 2X4 reconstruction , thus revealing the fundamental role of the interaction between the molecule and the reconstructed substrate in orenting the adsorbed molecules . In the case of HOPG the images indicate the formation of irregular channels thus suggesting an auto assembling of the molcules between themselves rather than a strong intraction with the substrate , as in the GAs case.