XX Congresso Brasileiro de Toxicologia, Goiânia, 08-11 Outubro 2017
Silva, MS; Facchini, G; Pinheiro, ALTA; Pinheiro, AS; Eberlin, S; Picon, FC; Eberlin, S.
Actives used in the treatment of dermatoses act on deeper tissues of the skin, being necessary to permeate the stratum corneum. On the other hand, skin permeation is undesirable in some products, such as sunscreens and repellents, constituting an important parameter indicative of product safety. FTIR technique is based on the principle of IR absorption by the active, resulting in characteristic vibrational movements in the molecule. In this sense, the use of FTIR is a useful tool in dermal safety assessments, where the objective is that the active does not permeate the stratum corneum (SC), and in evaluations of topical efficacy with the objective of skin permeation. Evaluate the skin permeation of topical products through FTIR-ATR using ex vivo skin fragments from elective plastic surgery. Icaridine and caffeine spectrum were measured using the IR spectrophotometer with ATR cell and ZnSe crystal. The baseline spectrum of skin fragments, actives (Icaridne/caffeine) and products were obtained and. The formulations containing each active were applied to the skin (2 mg/cm2). Spectrum measurements were obtained 1 hour (t1) minutes after application for Icaridine and 24 hours (T24) after application for Caffeine. After, 50 tape-stripping was performed for removal SC and new spectral reading. The spectrum obtained demonstrate the presence of active on the surface of skin in t15 and t60. After the 50 tape-stripping process we observed the absence of monitoring bands for Icaridine, which is an active used in repellents, confirming the absence of permeability in SC. For assessments of caffeine, an active ingredient commonly used in cosmetic products that accelerate the lipolysis process, we observed the presence of the monitoring bands even after removal of SC by tape-stripping technique, confirming its skin permeation ability. According to the results obtained, we can conclude that the use of the FTIR-ATR method together with the tape-stripping technique using human skin fragments for the identification of active skin permeation is a promising tool in safety and efficacy trials of cosmetic and dermatological products.
Actives used in the treatment of dermatoses act on deeper tissues of the skin, being necessary to permeate the stratum corneum. On the other hand, skin permeation is undesirable in some products, such as sunscreens and repellents, constituting an important parameter indicative of product safety. FTIR technique is based on the principle of IR absorption by the active, resulting in characteristic vibrational movements in the molecule. In this sense, the use of FTIR is a useful tool in dermal safety assessments, where the objective is that the active does not permeate the stratum corneum (SC), and in evaluations of topical efficacy with the objective of skin permeation. Evaluate the skin permeation of topical products through FTIR-ATR using ex vivo skin fragments from elective plastic surgery. Icaridine and caffeine spectrum were measured using the IR spectrophotometer with ATR cell and ZnSe crystal. The baseline spectrum of skin fragments, actives (Icaridne/caffeine) and products were obtained and. The formulations containing each active were applied to the skin (2 mg/cm2). Spectrum measurements were obtained 1 hour (t1) minutes after application for Icaridine and 24 hours (T24) after application for Caffeine. After, 50 tape-stripping was performed for removal SC and new spectral reading. The spectrum obtained demonstrate the presence of active on the surface of skin in t15 and t60. After the 50 tape-stripping process we observed the absence of monitoring bands for Icaridine, which is an active used in repellents, confirming the absence of permeability in SC. For assessments of caffeine, an active ingredient commonly used in cosmetic products that accelerate the lipolysis process, we observed the presence of the monitoring bands even after removal of SC by tape-stripping technique, confirming its skin permeation ability. According to the results obtained, we can conclude that the use of the FTIR-ATR method together with the tape-stripping technique using human skin fragments for the identification of active skin permeation is a promising tool in safety and efficacy trials of cosmetic and dermatological products.
