title: Rheological characterization of a xanthan-galactomannan hydrogel loaded with lipophilic substances.
abstract: We compared the structures and rheology of xanthan-galactomannan (X:G) hydrogels with the addition of curcumin in microemulsion (X:GMC) and ethanol (X:GEC). X:GMC hydrogels have gel characteristics and exhibited a significantly higher elastic response than the X:GEC and X:G hydrogels at room temperature, but after heating, an increase in the elastic modulus was observed for the last two systems. The visualization of the hydrogel microstructures by cryo-scanning electronic microscopy revealed pores within the lamellar structure only for X:GMC. In vitro skin permeation tests showed a more pronounced lag time for X:GMC; however, a more efficient permeation from X:GMC than from X:GEC. This study demonstrates that the X:G system is an alternative to traditional gels for the topical applications of hydrophobic drugs.
authors.affiliation: Department of Biochemistry and Molecular Biology, Federal University of Paraná, BP 19046, 81531-980 Curitiba, Paraná, Brazil.
authors.forename: Heidegrid S
authors.initials: HS
authors.lastname: Koop
authors.forename: Eneida J
authors.initials: EJ
authors.lastname: Da-lozzo
authors.forename: Rilton A
authors.initials: RA
authors.lastname: de Freitas
authors.forename: Célia R C
authors.initials: CR
authors.lastname: Franco
authors.forename: David A
authors.initials: DA
authors.lastname: Mitchell
authors.forename: Joana L M
authors.initials: JL
authors.lastname: Silveira
mesh_terms: D000279:Administration, Cutaneous; D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics; D003474:Curcumin / Q000008:administration & dosage* / Q000493:pharmacokinetics; D004337:Drug Carriers / Q000737:chemistry*; D005690:Galactose / Q000031:analogs & derivatives; D020100:Hydrogels / Q000737:chemistry*; D008351:Mannans / Q000737:chemistry*; D011135:Polysaccharides, Bacterial / Q000737:chemistry*; D012212:Rheology; D012867:Skin / Q000378:metabolism; D012869:Skin Absorption; D013552:Swine
chemical_list: D000970:Antineoplastic Agents; D004337:Drug Carriers; D020100:Hydrogels; D008351:Mannans; D011135:Polysaccharides, Bacterial; C012990:galactomannan; D003474:Curcumin; C002563:xanthan gum; D005690:Galactose