Synthesis, characterization and in vitro release studies of a new acetazolamideeHP-b-CD-TEA inclusion complex

GLADYS GRANERO; MARCOS MAITRE; CLAUDIA GARNERO; MARCELA LONGHI

EUROPEAN JOURNAL OF MEDICAL CHEMISTRY

ELSEVIER

Año: 2008 vol. 43 p. 464 - 470

0223-5234

Abstract The aim of our work was to develop a multicomponent inclusion complex of acetazolamide (ACZ) in order to investigate the combined effect of hydroxypropyl-b-cyclodextrin (HP-b-CD) and triethanolamine (TEA) on the solubility of ACZ and its possibility of ophthalmic delivery. Phase solubility study was used to evaluate the complexation in solution at 25 C. Complex formation was also evaluated by comparing the infrared (FT-IR) spectra of the solid complexes with a simple physical mixture containing the same amount of ACZ. FT-IR experiments provided data indicating that the carbonamido group of ACZ is involved in the inclusion process. In vitro release data showed that both formulations, containing the freeze-dried ternary complex and the corresponding simple physical mixture of ACZ with HP-b-CD and TEA presented the fastest release rate of ACZ. These results suggest that the ACZeHP-b-CDeTEA complex represents an effective novel formulation to enhance ACZ solubility in water, turning it promising for ophthalmic administration.b-cyclodextrin (HP-b-CD) and triethanolamine (TEA) on the solubility of ACZ and its possibility of ophthalmic delivery. Phase solubility study was used to evaluate the complexation in solution at 25 C. Complex formation was also evaluated by comparing the infrared (FT-IR) spectra of the solid complexes with a simple physical mixture containing the same amount of ACZ. FT-IR experiments provided data indicating that the carbonamido group of ACZ is involved in the inclusion process. In vitro release data showed that both formulations, containing the freeze-dried ternary complex and the corresponding simple physical mixture of ACZ with HP-b-CD and TEA presented the fastest release rate of ACZ. These results suggest that the ACZeHP-b-CDeTEA complex represents an effective novel formulation to enhance ACZ solubility in water, turning it promising for ophthalmic administration. Keywords: Acetazolamide; Topical preparation; Cyclodextrins; Triethanolamine; In vitro release studiesAcetazolamide; Topical preparation; Cyclodextrins; Triethanolamine; In vitro release studies