In vivo skin irritation testing
Skin allergy and irritation test was determined
follow in the test guideline (TG) No. 404 of OECD
guidelines for testing of chemicals (2001)(27). White
rabbits (New Zealand) were used for this testing. The
animal ethical committee of Prince of Sonkla University
approved this study. The epidermal hair at the back
area was removed in the range of 10 x 10 cm2
. A 0.5 mL
of sample (10% w/v of either liposome or un-formulated
Roselle solution) was poured on the gauze patch size
2.5 x 2.5 cm2
and applied on the hairless area of the
back of rabbit and the gauze patch was covered with
transpore adhesive tape for 4 hours. Distilled water 0.5
ml was used as control. The sample patch was removed
after 4 hours and the skin area of application was
cleaned. If any irritation of skin was observed, the level
of erythema and oedema at any time (1, 24, 48 and 72
hours) was recorded using guideline given in Table 1.
Statistical analysis
Results are expressed as the mean + SD of at
least three experiments. Analysis of variance (ANOVA)
was used to test the statistical significance of difference
among groups. Statistical significance in the difference
of the mean was determined by Dunnet’s method or