Background and Aim: Tretinoin has been formulated in different vehicles in
an attempt to decrease the irritation associated with the past formulations. So to improve
the skin uptake and reduce irritation of tretinoin, we need a carrier with an ability of skin
targeting. For achieving this purpose, nanostructured lipid carriers (NLCs) are chosen as
a new topical drug delivery system to improve the absorption and reduce side effects.
Method: Cetyl alcohol and isopropyl myristate was selected as the lipid of NLC.
Polysorbate 80 was used as the surfactants to stabilize NLC. The hot homogenization
method was performed to prepare the tretinoin loaded NLC. The various formulations
were characterized by photon correlation spectroscopy. Atomic Force Microscopy and
Transmission Electron Microscopy were used to study particle morphology. Drug entrapment
efficiency and safety of the drug delivery system were examined.
Result: The results indicated almost the full loading of tretinoin in the NLC and the validity
of the production method. The in vitro release studies demonstrated that the product
was a slow- release one which affects reducing side effects and improves the
effectiveness of tretinoin. Human patch test of tretinoin loaded NLC was done and the
result was completely safe.
Conclusion: The in vitro
release studies showed that NLC containing tretinoin has prolonged
profile as compared to commercially available tretinoin creams. It appears that
the prolong release profile sustains permeation and absorption of tretinoin and also provides