Solid lipid nanoparticles as carriers of hydrocortisone and progesterone complexes with beta-cyclodextrins

Inclusion complexes of hydrocortisone and progesterone were formed with bet a-cyclodextrin or 2-hydroxypropyl-beta-cyclodextrin. The formation of the c omplexes was confirmed by differential scanning calorimetry (DSC). The incl usion complexes were incorporated in two types of solid lipid nanoparticles (SLN). In the presence of the complexes the sizes of SLN remained below 10 0 nm. DSC analysis showed that hydrocortisone and progesterone are disperse d in SLN in an amorphous state. Using the beta-cyclodextrin complexes the i ncorporation of the more hydrophilic drug, hydrocortisone, was higher than that of progesterone. Release of hydrocortisone and progesterone from SLN w as lower when they were incorporated as inclusion complexes than as free mo lecules. (C) 1999 Elsevier Science B.V. All rights reserved.