Tag Archives: bioavailability

Physical and Chemical Study of Simvastatin Inclusion Complexes

Rédai Emőke1, Tőkés B.2, Kiss A.3, Sipos Emese1, Ciurba Adriana1, Todoran Nicoleta1

1 Pharmaceutical Technology Department, Faculty of Pharmacy, University of Medicine and Pharmacy Tîrgu Mureș
2 Physical Chemistry Department, Faculty of Pharmacy, University of Medicine and Pharmacy Tîrgu Mureș
3 Organic Chemistry Department, Institute of Chemistry, Faculty of Science and Technology, University of Debrecen

Background: Simvastatin is an inhibitor of hydroxy-methyl-glutaryl-coenzyme A reductase, used in the treatment of hypercholesterolemia.
Aim: To enhance his bioavailability through inclusion complexation, as host molecule hydroxypropyl-b-cyclodextrin had been used. The objective of this study is to present our results of the study of some simvastatin and hydroxypropil-b-cyclodextrin (HPbCD) inclusion complexes. We analyzed the products by phase solubility study, dissolution test and Fourier-transformed Infrared Spectroscopy (FT-IR).
Methods: Complexes were prepared by kneading molecular ratios of 1:1 and 1:2 and compared also with physical mixtures. Solubility studies were performed in the presence of various HPbCD concentrations and the stability constant was calculated. The inclusion complexation was evaluated by dissolution and Fourier transformed infrared spectroscopy.
Results: When compared with the pure drug, the dissolution of simvastatin is improved in the presence of b-cyclodextrin derivates, depending on the complex preparation method.
Conclusions: The solubility of simvastatin increases as a function of HPbCD concentration. FT-IR study suggests the presence of intermolecular hydrogen bonds between simvastatin and HPbCD in inclusion complex.

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Physical and Chemical Study of Lovastatin Inclusion Complexes. Bioavailability Improvement

Rédai Emőke1,Tőkés B2, Sipos Emese1

1 Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Medicine and Pharmacy, Tîrgu Mureș, Romania
2 Department of Physical Chemistry, Faculty of Pharmacy, University of Medicine and Pharmacy, Tîrgu Mureș, Romania

Background: Lovastatin is an inhibitor of hydroxy-methyl-glutaryl-coenzyme A reductase, used in the treatment of hypercholesterolemia. To enhance its bioavailability through inclusion complexation, as host molecule hydroxypropyl-b-cyclodextrin had been used.
Methods: Complexes were prepared by kneading in molecular ratio 1:1 and compared also with a physical mixture in molecular ratio 1:1. The complex was studied by performing dissolution tests and differential scanning calorimetry.
Results: Mixing the drug with the host molecule the soluble amounts were increased to 1.55 mg in artificial gastric juice and 2.99 mg in artificial intestinal juice. Kneading also improved the solubility of lovastatin to 1.94 mg in artificial gastric juice and 2.78 mg in artificial intestinal juice. In the thermograms a sharp endotherm peak was observed at the same position of lovastatin.
Conclusions: Dissolution studies showed an improvement of the drug release both in artificial gastric and intestinal juice. The sharp endotherm peak on the DSC curves indicates the untrapped lovastatin.

Keywords: , , ,
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