165
profiles [10, 11]. Other DSC studies on drug-CD complexes
include methyl-β-cyclodextrin (M-β-CD) with lidocaine and
2-HP-β-CD with oxicams [12, 13]. In all these cases, each component and each complex or mixture were analyzed and through
comparison, an estimation of the nature and degree of interactions
was obtainable. DSC generally provides an insight into the system
thermodynamics, which complements classic pharmaceutical formulation tests, such as phase solubility, dissolution studies, and in
vitro permeability.
Sartans and specifically irbesartan and losartan have been characterized by DSC analysis [14–17]. In addition, the complex
between valsartan and β-cyclodextrin (β-CD) was prepared by various methods, i.e. solid dispersion, freeze-drying, kneading and
physical mixture, and studied by DSC [18]. The reduction of crystallinity of the system is an indication of the complexation between
the two materials and is reflected on the observed peaks in the
calorimetric profile, where the melting transition of the drug molecule is diminished or vanished.
2 Materials
The materials described below are referred to the DSC analysis of
sartan-2-HP-β-CD mixtures or complexes or the components
Fig. 2 Thermogram of an amorphous compound showing glass transition (T g ), crystallization (T c ), melting (T m )
and degradation
DSC on Sartan/Cyclodextrin Delivery Formulations
profiles [10, 11]. Other DSC studies on drug-CD complexes
include methyl-β-cyclodextrin (M-β-CD) with lidocaine and
2-HP-β-CD with oxicams [12, 13]. In all these cases, each component and each complex or mixture were analyzed and through
comparison, an estimation of the nature and degree of interactions
was obtainable. DSC generally provides an insight into the system
thermodynamics, which complements classic pharmaceutical formulation tests, such as phase solubility, dissolution studies, and in
vitro permeability.
Sartans and specifically irbesartan and losartan have been characterized by DSC analysis [14–17]. In addition, the complex
between valsartan and β-cyclodextrin (β-CD) was prepared by various methods, i.e. solid dispersion, freeze-drying, kneading and
physical mixture, and studied by DSC [18]. The reduction of crystallinity of the system is an indication of the complexation between
the two materials and is reflected on the observed peaks in the
calorimetric profile, where the melting transition of the drug molecule is diminished or vanished.
2 Materials
The materials described below are referred to the DSC analysis of
sartan-2-HP-β-CD mixtures or complexes or the components
Fig. 2 Thermogram of an amorphous compound showing glass transition (T g ), crystallization (T c ), melting (T m )
and degradation
DSC on Sartan/Cyclodextrin Delivery Formulations