.8 - Methoxypsoralen Skin And Evaluation Of Targeted Nano-liposomes Gel

Vitiligo is a condition in which the tyrosine system in pigment cells are destroyed , resulting in irregularly shaped white patches on the skin. We studied the preparation craft, skin-targetting property, the quality standard and the initial stability of 8-methoxyposoralen (MOP) liposome and liposomal gel, in order to prepare a skin targetting liposome gel of MOP with more effective and fewer side effects. We also studied the mechanic and influencing factors of skin-targetting property, aiming to prepare a more effective Vitiligo drug with fewer side effects.Film-supersonic method was better than antiphase evaporating method, film-dispersion method , and aether infusion method in preparating MOP liposome, which was evaluated with envelopment efficiency (EE) and mean diameter. High pressure homogeneous method was first used in preparating MOP nanoliposome by homogenizing 6 times at 1000 bar pressure. Carbopol 940 was used as matrix in preparating MOP liposome gel, in which liposome was added before the gel formed. The quality of liposome and liposomal gel were evaluated in general.The liposome had a fine-looking outward appearance, narrow size-distribution under the transmission electron microscope (TEM) and in laser diffraction particle size analyzer. The mean diameter of liposome and liposomal gel was 280 nm and 332.8 nm respectively. The appearance of liposomal gel was characterized by freeze-etching technique. The EE of five batches of liposomes was 94.2%, 97.5%, 93.4%, 95.3% and 95.7% respectively. That of the two batches of liposomal gel was 91.5% and 87.7% respectively, which were determined with sephadex column-HPLC method. The content of MOP in the liposome and liposomal gel was 2.96, 2.82, 2.88, 3.03, S.llmg.mL^-1 and 1.82, 1.93 mg. g^-1 respectively. The liposome and the liposomal gel were stable after 90 days at 4℃ or 25 ℃, but they were unstable at high temperature (40℃) and under strong light (4000⁵000LX) condition.The transdermal permeability in vitro of MOP liposome through mouse skin was tested. The drug detained in the skin was 2.7 times and...