title: In vitro and in vivo evaluation of a novel testosterone transdermal delivery system (TTDS) using palm oil base.
abstract: Transdermal preparations for testosterone are becoming popular because of their unique advantages such as avoidance of first-pass effect, convenience, improved bioavailability, and reduction of systemic side effects. A novel testosterone transdermal delivery system (TDDS) was developed using a palm oil base called HAMIN™ (a commercial product) and tested using in vitro and in vivo skin permeability test methods.
  
  
  METHODS
  The physical characteristics of the formulation such as particle size and viscosity were determined by using Franz diffusion cell and Brookfield viscometer, respectively. In vivo skin permeability test was performed on healthy rabbits through the skin. Testosterone in serum was analyzed using the validated Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) technique.
  
  
  RESULTS
  In vitro study showed that the cumulative amount of testosterone diffused was between 40 to 1400 ngcm(-)² over a period of five hr after application of TDDS through the artificial Strat-M™ membrane. In the in vivo rabbit skin permeability test, the results indicated that testosterone was well absorbed with a mean Cmax and Tmax of 60.94 ngml(-1) and 2.29 hr after application of TDDS while no increase was observed in placebo treatment. Particle size analysis ranged from 79.4 nm to 630.0 nm for placebo and 97 to 774.0 nm for TDDS.
  
  
  CONCLUSIONS
  The formulation was successfully prepared using HAMIN™, which has demonstrated great potential for topical delivery of testosterone.
authors.affiliation: Shimadzu-UMMC Center for Xenobiotics Studies (SUCXeS), University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Didi Erwandi Mohamad
authors.initials: DE
authors.lastname: Haron
authors.affiliation: Shimadzu-UMMC Center for Xenobiotics Studies (SUCXeS), University of Malaya, 50603 Kuala Lumpur, Malaysia; University of Malaya Bioequivalence and Testing Center (UBAT), Department of Pharmacology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Zamri
authors.initials: Z
authors.lastname: Chik
authors.affiliation: Department of Pharmacy, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Mohamed Ibrahm
authors.initials: MI
authors.lastname: Noordin
authors.affiliation: University of Malaya Bioequivalence and Testing Center (UBAT), Department of Pharmacology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Zahurin
authors.initials: Z
authors.lastname: Mohamed
keywords: HAMIN™; Skin permeation; Testosterone; Transdermal delivery-; system