search by
Copyright @ Pol J Cosmetol
Pol J Cosmetol 2015, 18(4): 303-308pl  Effect of semisolid base on release, permeation and skin retention of salicylic acidAndrzej Jankowski, Renata Dyja, Dorota Sobocińska Zakład Technologii Postaci Leku, Katedra Farmacji Stosowanej, Śląski Uniwersytet Medyczny w Katowicach Summary Introduction. Topical semisolid formulations of salicylic acid are widely used in dermatological conditions. The vehicle in which salicylic acid is applied to the skin may influence its cutaneous bioavailability and skin permeation. The therapeutic efficacy of salicylic acid requires increased skin retention but the salicylic acid permeation through the skin should be limited by semisolid bases in order to prevent the occurrence of toxic effects (salicylism). Aim. The aim of the study was to investigate the influence of semisolid bases on the release, skin permeation and skin retention of salicylic acid. Material and methods. Six different 5% semisolid formulations of salicylic acid were prepared. The semisolid bases included in the study were: two hydrophilic bases (macrogol ointment, hydrogel), two hydrophobic bases (absorption ointment I, absorption ointment II) and two various emulsion bases (hydrophilic cream I and hydrophilic cream II). The studies on the release, skin permeation and retention of salicylic acid from semisolid formulations were conducted via paddle over extraction cell method. The skin permeation and retention studies were conducted with porcine ear skin as a model membrane. Results. Hydrogel and absorption ointment I provided the highest increase in salicylic acid skin retention. The limitation of salicylic acid skin permeation was achieved with absorption ointment II. Absorption ointment I, absorption ointment II and hydrogel provided the highest increase in retention/permeation ratio of salicylic acid. It has been shown that there is a moderate correlation between the release of salicylic acid and its permeation through the skin (r=0.631). Conclusions. Absorption ointment I composed of castor oil and lanolin is an optimal semisolid base for salicylic acid. The improvement of retention/permeation ratio may be achieved with semisolid bases containing propylene glycol or castor oil. Key words: semisolid formulation, salicylic acid, release, skin permeation, skin retention |