Statistical optimization of a sustained-release matrix tablet of lobenzarit disodium

The statistical optimization of sustained-release matrix tablets of lobenzarit disodium salt (LDS) was performed using the central composite experiment design 2³ for three independent variables: the amount of polymer (Eudragit® RS-PO) AP, the total volume of granulation solvent VS, and the amount of filler (microcrystalline cellulose) CE. The t_90% was selected as the response variable. The response surfaces were performed from a statistical mathematical model. The optimal formulation was obtained for the variables (AP = 15 mg, VS = 60 μl, and CE = 0).     

Multifactorial analysis in the study of hydroformylation of oct-1-ene using supported aqueous phase catalysis

The influence of the hydration and the surface characteristics of five supports in the hydroformylation of oct-1-ene by supported aqueous phase catalysis (SAPC) using [Rh₂(μ-S^tBu)₂(CO)₂(TPPTS)₂] as catalyst was studied. The results confirm that the size of the pores and the amounts of water were found to be the determining factors contributing to the SAPC. According to the size of pores there is a critical value for which the SAPC takes place either in the classical model or in conditions where the pores are filled. When the pores are fully filled the SAPC can operate efficiently onto the external surface, stabilising the conversion in a relatively wide range of support hydration.