Tretinoin Cream

TretinoinCream （50mg/100g） 1.Formulation I.Tretinoin（BASF）......................................0.05g Luvito lEHO[1].........................................8.0g II.CremophorA6[1]....................................3.0g CremophorA25[1]..................................1.5g Glycerolmonostearate..............................3.0g Cetylalcohol............................................3.0g Tegiloxan100（Goldschmidt）...................0.5g III.Butylhydroxyto luene...............................0.04g Propyleneglycol[1]..................................4.0g Preservatives...........................................0.5g Perfumes.................................................0.2g Water.....................................................76.2g 2.Manufacturing SeparatelypreparesolutionIandmixtureIIbyheatingto about75C. HeatmixtureIIIuntilaclearsolutionisformed.to thewarmmixtureII addsolutionI,thenmixtureIIIandcoolbystirring. 3.Chemicalstability（20–25C,dark） MonthsTretinoincontentLossoftretinoin 00.046% 30.047%0% 60.046%0% 90.047%0% 120.047%0% Analyticalmethod:Spectrophoto metricat358nminchloroform 2-propanol1 1（E1%/1cm=1,480）4. RemarkIt is important to protect the gel against light to avoid the isomerizationanddegradation of tretinoin.