ABSTRACT
Objective To evaluate the skin irritation of eucalyptus oil and its in vivo transdermal penetration enhancement properties by using the cutaneous microdialysis technique. Methods The CCK-8 assay was used to measure the toxicity of eucalyptus oil on HaCaT cells, and the TEWL values of the rat skin was determined to investigate the effect of eucalyptus oil on the skin integrity and irritation. Ligustrazine and geniposide were chosen as lipophilic and hydrophilic model drugs, respectively, and their microdialysis probe in vivo recoveries were determined using the retrodialysis method. After treatment with eucalyptus oil, the skin pharmacodynamics behaviors of two model drugs were investigated to evaluate its penetration-enhancement activity. Results The cytotoxicity test revealed there IC50 value of eucalyptus oil to HaCaT cells was 2.452 mmol/L, which was significantly higher than that of chemical penetration enhancer Azone (IC50, 0.266 mmol/L). Meanwhile, the eucalyptus oil had a certain impact on the rat skin TEWL values, but it was weaker than Azone, this implied that the eucalyptus oil had a mild skin irritation. The in vivo transdermal microdialysis tests revealed that the enhancement ratios (ER) of ligustrazine and geniposide were 11.40 and 13.79, respectively, indicating that eucalyptus oil could effectively facilitate the transdermal permeation of both of lipophilic and hydrophilic drugs. Although the penetration enhancement property was generally weaker than Azone, the ER value of eucalyptus oil was closely approximate to Azone. Conclusion The eucalyptus oil could promote the transdermal permeation of both lipophilic and hydrophilic drugs with mild skin irritation, which provided the data support for its application in topical preparation.
ABSTRACT
Objective: To investigate the changes of matrine concentration in rat local skin with time after transdermal administration of matrine transfersomes, and to evaluate the transdermal delivery properties. Methods: The matrine transfersomes were applied non-occlusively onto rat skin in vivo with abdominal hair removal, and the concentration of drugs in microdialysate of skin was detected by microdialysis and reverse phase high performance liquid chromatography. Furthermore, the concentration-time curves of matrine in microdialysates of skin were compared among marine transfersomes, liposomes, and deoxysodium cholate solution. Results: After the transfersomes were given to rats, the maximum peak time (tmax) of matrine skin concentration appeared at (4.200 ± 0.447) h. The maximum skin concentration (Cmax) was (0.927 ± 0.251) μg/mL and area under the curve (AUC0-8) was (5.033 ± 1.526) μg·h·mL-1, which were much higher than those of the liposomes and the solution (containing 0.8% sodium deoxycholate, P < 0.05), while tmax shortened much more than that of them. Conclusion: In vivo skin microdialysis could be used to assess the transdermal delivery properties of matrine transfersomes. And matrine transfersomes have the good transdermal permeability and efficacy.