Preparation and characterization of marine sponge collagen nanoparticles and employment for the transdermal delivery of 17beta-estradiol-hemihydrate

Drug Dev Ind Pharm. 2009 Sep;35(9):1035-42. doi: 10.1080/03639040902755213.


Background: Transdermal administration of estradiol offers advantages over oral estrogens for hormone replacement therapy regarding side effects by bypassing the hepatic presystemic metabolism.

Aim: The objective of this study was to develop nanoparticles of Chondrosia reniformis sponge collagen as penetration enhancers for the transdermal drug delivery of 17beta-estradiol-hemihydrate in hormone replacement therapy.

Method: Collagen nanoparticles were prepared by controlled alkaline hydrolysis and characterized using atomic force microscopy and photon correlation spectroscopy. Estradiol-hemihydrate was loaded to the nanoparticles by adsorption to their surface, whereupon a drug loading up to 13.1% of sponge collagen particle mass was found. After incorporation of drug-loaded nanoparticles in a hydrogel, the estradiol transdermal delivery from the gel was compared with that from a commercial gel that did not contain nanoparticles.

Results: Saliva samples in postmenopausal patients showed significantly higher estradiol levels after application of the gel with nanoparticles. The area under the curve (AUC) for estradiol time-concentration curves over 24 hours was 2.3- to 3.4-fold higher and estradiol levels 24 hours after administration of estradiol were at least twofold higher with the nanoparticle gel.

Conclusions: The hydrogel with estradiol-loaded collagen nanoparticles enabled a prolonged estradiol release compared to a commercial gel and yielded a considerably enhanced estradiol absorption. Consequently, sponge collagen nanoparticles represent promising carriers for transdermal drug delivery.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Absorptiometry, Photon
  • Administration, Cutaneous
  • Aged
  • Animals
  • Biological Availability
  • Collagen / chemistry*
  • Dialysis
  • Drug Carriers
  • Electrochemistry
  • Estradiol / administration & dosage*
  • Estradiol / pharmacokinetics*
  • Excipients
  • Female
  • Humans
  • Hydrogels
  • Microscopy, Atomic Force
  • Middle Aged
  • Nanoparticles
  • Particle Size
  • Porifera / chemistry*
  • Saliva / metabolism
  • Thermodynamics


  • Drug Carriers
  • Excipients
  • Hydrogels
  • Estradiol
  • Collagen