Publications (2)7.49 Total impact
-
Article: Tablet preformulations of indomethacin-loaded mesoporous silicon microparticles.
[show abstract] [hide abstract]
ABSTRACT: In this study, indomethacin-loaded thermally oxidized mesoporous silicon microparticles (TOPSi-IMC) were formulated into tablets with excipients in order to improve the dissolution and permeability properties of the poorly soluble drug. Formulations of TOPSi-IMC particles and excipients were prepared at different TOPSi-IMC particle ratios (25, 30 and 35%). The formulations were compressed by direct compression technique with a single punch tablet machine. For comparison, a formulation containing the bulk IMC (indomethacin) and the same excipients without thermally oxidized mesoporous silicon microparticles particles (TOPSi) was prepared and compressed into tablets. The TOPSi-IMC tablets were characterised according to weight, thickness, crushing strength, disintegration time and dissolution rate. The results of this study show that TOPSi-IMC particles can be compressed to a conventional tablet. The release rate of the drug and its permeation across intestinal cells model (Caco-2) from TOPSi-IMC tablets was improved compared to the bulk IMC tablets. The dissolution rate and permeability of IMC from the tablets decreased with increasing ratio of the TOPSi-IMC particles in the formulation. The phenomenon is, presumably, a result of the loss of unique pore structure of the particles due to deformation of the particles under the compression load.International journal of pharmaceutics 10/2011; 422(1-2):125-31. · 2.96 Impact Factor -
Article: Preparation of cellulose samples for size-exclusion chromatography analyses in studies of paper degradation.
[show abstract] [hide abstract]
ABSTRACT: Hydrolytic degradation of cellulose was shown to take place during the activation procedure in distilled water during the dissolution procedure of cellulose samples from papers for size-exclusion chromatography analyses in the lithium chloride-N,N-dimethylacetamide (DMAc) solution system. The use of dilute aqueous sodium hydroxide solution in the activation procedure prevents hydrolytic degradation of cellulose during the dissolution procedure, especially in the case of samples of aged papers with low pH. The use of the freeze-drying technique provides samples of cellulose ready-made for dissolution in lithium chloride-N,N-dimethylacetamide solution.Journal of Chromatography 09/2003; 1008(2):129-34. · 4.53 Impact Factor
Top co-authors
Top Journals
Institutions
-
2003–2011
-
University of Helsinki
- • Division of Pharmaceutical Technology
- • Laboratory of Polymer Chemistry
Helsinki, Province of Southern Finland, Finland
-
