efficacy of isotretinoin-loaded solid lipid nanoparticles in comparison to Isotrex on acne treatment

Topical retinoids are considered as the first line therapy in the treatment of acne vulgaris, but they are associated with cutaneous irritation. In this study, isotretinoin-loaded solid lipid nanoparticles [IT-SLN] were prepared to treat the mild to moderate acne. Also using IT-SLN would minimize IT adverse effects in comparison to commercial product, Isotrex. This study was conducted to prepare and characterize IT-SLN and assessing the efficiency of IT-SLN comparing to Isotrex acne. IT-SLN was prepared using hot high pressure homogenization method. IT-SLN contained 0.05% IT in 5% of lipid phase [Glyceryl monostearate- GMS] and tween 80 [2.5% w/v] was used as surfactant in the aqueous phase. IT-SLN was characterized by particle size analyzing, differential scanning calorimetry and transmission electron microscopy. Encapsulation efficacy was also obtained using spectrophotometry. The efficacy of IT-SLN was evaluated in a randomized, single-blind, parallel-group study and compared with Isotrex. Forty patients encountered in the study and divided in two groups. Treatment regimen was once-nightly topical administration accompanied with topical administration of clindamycin 2% solution twice a day for 8 weeks. The particle size of IT-SLN was around 60 nm with PDI of 0.4 and zeta potential was about -40 mV. Encapsulation efficacy of IT in SLN in crystalline form was 84 +/- 0.21%. IT-SLN produced significantly better treatment than Isotrex in both non-inflammatory and inflammatory lesions according to its recovery percent after 8 weeks. Also IT-SLN gained better global assessment scores. Our results showed that IT-SLN had higher efficacy than Isotrex to clear non-inflammatory and inflammatory lesions

evaluation of [sun protection factor] SPF accuracy of some sunscreens

The prevalence of photo-aging and skin cancers has been increasing in many parts of the world. To reduce cutaneous photodamage and skin carcinogenesis, primary prevention that an integral component of it is the use of sunscreens is recommended. The aim of this study was assessment of SPF accuracy in some Iranian sunscreens. Among healthy individuals with skin types I to III, 25 volunteers enrolled, but finally ten persons for two sunscreens "X" and "Y" completed the study. Candidates were tested during three days using phototherapy UV 800 K with UV B lamps, UV skin-tester and UV-meter [Waldman Company, Germany]. Minimal erythemal dose in unprotected areas of the skin [MEDup] was initially measured and then in protected areas [MEDp] was determined, according to the MEDup amount and national sunscreens' SPF label [SPF30]. Volunteer was exposed to his own MEDp and also 85% of it, after 24 hours, the two areas were examined for erythema. The final test result declared "correct", for the tested cream, if the accuracy of the SPF was confirmed in at least 90% of volunteers. The accuracy of test was confirmed according to SPF assessment standard protocol. All the candidates were male with mean age of 33.5 +/- 8.51 yrs. The MED mean was 73/09 +/- 15/6 mj/cm2. Final results declared "correct" for both products. In addition, the standard lotion test result was correct for all candidates. According to the results, we can assure people and physicians about reliability of labeled SPF, at least in some of the national products