Ciaftalan zinc

The preparation of new photosensitizers and studies on photodynamic therapy (PDT) have provided promising results and realistic expectations for an efficient medical treatment. Phthalocyanines (Pcs) have become extremely attractive for this purpose owing to their molecular versatility and superior physicochemical properties. Motivated by these facts, in this study, non-peripherally substituted zinc(II) Pc (2) was prepared by cyclotetramerization of the phthalonitrile derivative bearing 3-methoxybenzyloxy units. Also, physicochemical and in vitro analyses were completed. In photochemical studies, the obtained singlet oxygen quantum yield (Φ_Δ) values were 0.73 in dimethylsulphoxide (DMSO) and 0.55 in dimethylformamide (DMF). Theoretical calculations based on density functional theory (DFT) provide valuable information on the energies and character of the electronic excitations, thus allowing a prediction of their potential applicability to generate singlet oxygen. The PDT activity of the zinc(II) phthalocyanine bearing 3-methoxybenzyloxy substituents was tested via in vitro studies using the human colon cancer cell lines. In cytotoxicity experiments, the most effective incubation time for cell lines was found to be 24 h, and the most effective concentration was 8 μM. Furthermore, the cell viability rate decreased significantly with the increasing power density. The results suggested that the newly synthesized zinc(II) Pc is an effective photosensitizer with potential use for the treatment of colon cancer.

Exchange bias is exptl. realized when the magnetization loop is shifted from the zero magnetic field, and used in spin valve sensors to pin their hard reference layer, nullifying the subsequent effect of any variation in the sensor layers.In this regard, fundamental insights into magnetic behavior of sufficiently thin films are important for tuning their properties, and are critical for better understanding of surface phenomena in nanodevices.Here, the hysteresis loop shift phenomenon is investigated for nanoscale ferromagnetic-mol. layers using a superconducting quantum interference device (SQUID) over a wide temperature range (2-300 K).Two heterostructure systems consisting of cobalt (Co) nanolayers in contact with metal-free phthalocyanine (H₂Pc) planar and fullerene (C60) spherical mols. are fabricated using organic mol. beam epitaxy and thermal evaporation methods, demonstrating the effect of surface phenomena on magnetic characteristics.For two stacks of Co/ H₂Pc and Co/ C₆₀ mol. layers, SQUID measurements indicate the presence of interfacial unidirectional anisotropy (i.e., the anisotropy that is effective only in one direction at the interface between thin films) in the temperature range below 20K.The magnitude of the strength of interactions through the shift and coupling energy is computed for both hybrid stacks, and compared with that for Co-magnetic and nonmagnetic transition metal H2Pc structures.Therefore, the influence of magnetic hardening of H₂Pc and C₆₀ mol. layers is confirmed for the bias field.By contrast, antiparallel spin alignment inside the mol. layer results from magnetic ions in the organic layer detached from the contact area, being responsible for large value of exchange bias.Accordingly, such heterostructured layers may act as pinning sites, paving the way for designing cost effective mol. spintronics and spin logic devices with faster data processing, ecofriendly, and high flexibility.