On the existence of a paramagnetic adduct of Ni(II)-bis-(di-n-butyl-diselenocarbamate). An EPR study

Paramagnetic adduct formation of pyridine with nickel(II)-bis(di-n-butyl-diselenocarbamate) is observed by means of EPR at 27°K. The low value of the zero field splitting and the g-factor are explained by strong spin-orbit interactions and by high covalency typical of the Se4-coordination sphere. © 1973

Razvoj matriksnih sustava za transdermalnu isporuku pentazocina: In vitro/in vivo ispitivanje

The present study aimed to develop hydroxypropyl methylcellulose based transdermal delivery of pentazocine. In formulations containing lower proportions of polymer, the drug released followed the Higuchi kinetics while, with an increase in polymer content, it followed the zero-order release kinetics. Release exponent (n) values imply that the release of pentazocine from matrices was non-Fickian. FT-IR, DSC and XRD studies indicated no interaction between drug and polymer. The in vitro dissolution rate constant, dissolution half-life and pharmacokinetic parameters (Cmax, tmax, AUC(s), t1/2, Kel, and MRT) were evaluated statistically by two-way ANOVA. A significant difference was observed between but not within the tested products. Statistically, a good correlation was found between per cent of drug absorbed from patches vs. Cmax, and AUC(s). A good correlation was also observed when per cent drug released was correlated with the blood drug concentration obtained at the same time point. The results of this study indicate that the polymeric matrix films of pentazocine hold potential for transdermal drug delivery.U radu je opisan razvoj transdermalnih sustava na bazi hidroksipropil metilceluloze za isporuku pentazocina. U pripravcima koji sadrže manje udjele polimera, otpuštanje lijeka slijedilo je Higuchijevu kinetiku. Međutim, ako je udio polimera veći oslobađanje je najbolje odgovaralo kinetici nultog reda. Vrijednost eksponenta n implicira da oslobađanje pentazocina iz matriksa nije po Fickovom zakonu. FT-IR, DSC i X RD studije ukazuju da nema interakcije između ljekovite tvari i polimera. In vitro konstanta oslobađanja, poluvrijeme oslobađanja i farmakokinetički parametri (Cmax, tmax, AUC(s), t1/2, Kel, i MRT) procijenjeni su statistički koristeći ANOVA program. Značajna razlika primijećena je između, ali ne i unutar testiranih pripravaka. Pronađena je dobra korelacija između lijeka apsorbiranog iz flastera i Cmax i AUC(s) te oslobođenog lijeka i koncentracije lijeka u krvi. Rezultati ukazuju da su polimerni matriksni filmovi pentazocina potencijalno dobri sustavi za transdermalnu primjenu lijeka

On the existence of a paramagnetic adduct of Ni(II)-bis-(di-n-butyl-diselenocarbamate). An EPR study

Paramagnetic adduct formation of pyridine with nickel(II)-bis(di-n-butyl-diselenocarbamate) is observed by means of EPR at 27°K. The low value of the zero field splitting and the g-factor are explained by strong spin-orbit interactions and by high covalency typical of the Se4-coordination sphere. © 1973

On the existence of a paramagnetic adduct of Ni(II)-bis-(di-n-butyl-diselenocarbamate). An EPR study

Paramagnetic adduct formation of pyridine with nickel(II)-bis(di-n-butyl-diselenocarbamate) is observed by means of EPR at 27°K. The low value of the zero field splitting and the g-factor are explained by strong spin-orbit interactions and by high covalency typical of the Se4-coordination sphere. © 1973

On the existence of a paramagnetic adduct of Ni(II)-bis-(di-n-butyl-diselenocarbamate). An EPR study

Paramagnetic adduct formation of pyridine with nickel(II)-bis(di-n-butyl-diselenocarbamate) is observed by means of EPR at 27°K. The low value of the zero field splitting and the g-factor are explained by strong spin-orbit interactions and by high covalency typical of the Se4-coordination sphere. © 1973

Photoacoustic Study of the Interaction Between Thin Oil Layers with Water

In the presented paper the structural changes in thin olive oil layers taking place as a result of interaction with water using a photoacoustic technique were studied. The oil layers were spread from a solution in a volatile solvent (ethyl ether) on the water and copper surface. These studies are a natural continuation of the previous work on a layered system performed within the light range (680 nm), which pointed to the irregularities of oil layers related to their thickness is now expanded to the infrared band. A structural irregularity was observed for a layer thickness of 100 μm, but it did not appear for the one of pure bulk oil. Signatures of irregularity were clearly observed in the phase plots whereas the amplitude dependences were not sensitive to them. The performed studies allowed one to relate the diversity of thermal parameters in the samples with structural changes found in oil layers originated from oil-water interactions