| 摘要: | 防曬成分經紫外線（Ultraviolet, UV）照射後會產生不穩定及結構改變的結果，使防曬效果降低，且導致皮膚敏感等症狀。防曬產品並不能完全阻隔UV，但部份UV穿透至皮膚後，誘發Reactive Oxygen Species (ROS)自由基的產生；這些游離的自由基與細胞作用使細胞損傷。本研究以化學性防曬劑及物理性防曬劑，來探討防曬劑間防曬係數（Sun Protection Factor, SPF）值的變化及相互的加乘作用；尋求有高SPF值及紫外線A （Ultraviolet A,UVA）防護力的最佳組合，並能降低配方中防曬成份之研究。本實驗將不同防曬成份添加在兩種乳化劑型：水中油型（O/W）及油中水型（W/O）配方中，探討相同比例的防曬成分在不同乳化劑型中，對紫外線的防禦力。
利用Labsphere UV1000S防曬係數測定儀，測定體外（in vitro）
SPF值；利用質體DNA與H2O2經UV照射引起損傷的保護力，來模擬人體的光保護性；接著利用人體紫外線照射儀在受測者皮膚產生的最小紅斑量（Minimal Erythema Dosage, MED），確認防曬乳使用在人體（in vivo）對UV的防禦力。再添加有抗氧化及抗自由基的三種中草藥於防曬乳，觀察SPF值的變化，紅斑及黑色素產生的情形。
添加3%Parsol MCX，2%Parsol 1789及純含量5%TiO2的防曬乳，在O/W劑型中：體外可測得SPF值33.21；W/O劑型中，in vitro可測得SPF值51.99。以質體DNA與H2O2經UV照射引起損傷的保護結果顯示：SPF值13.2 有18.05%，SPF值33.21有50.89%，所以較高SPF值的防曬乳，在紫外線B波長照射下，有較高的防護力。in vivo結果顯示：含3%Parsol MCX，2%Parsol 1789及純含量5%TiO2的防曬乳，在不同乳化劑型(O/W ,W/O)中有類似的SPF值12；且SPF數值愈高，in vitro與in vivo差異愈大。含1%中草藥HA防曬乳，in vivo可提升SPF值高於14.4 。
從體外及人體的實驗的結果，相同的防曬劑雖然W/O相較於O/W測試有優於近SPF值20的差異性，在人體沒有相同的結果；若相信in vitro高SPF值的防禦力，可能造成嚴重灼傷。質體DNA的保護實驗卻可讀出防曬乳，對皮膚的防護力，可為不易取得的受測者，提供便利的實驗模組；且此實驗的結果較in vitro接近in vivo。 含1%中草藥HA防曬乳，在 in vitro的SPF值未增加；但in vivo紅斑發生的時間明顯的延長；且紅斑持續的時間變短。因此在防曬產品設計時，in vitro的SPF值僅供參考，因為它無法判讀紅斑及細胞的損傷；這些是光老化及皮膚癌的警訊。
所以使用適量防曬成份再添加中草藥HA的防曬乳可達到高防護力的配方組成，期待為未來防曬產品的主流。
According previous studies show ultraviolet filters after UV irradiation that they be destruct and unstable. The results degrade sunscreen effect also penetrate to skin getting irritation symptom. We know that sunscreen products can’t offer absolutely isolation from UV damage; partial UV penetrates to induce ROS free radical reaction in skin. Between free radical and cell mediation cause cell damage. In this study , Both oil in water emulsion(O/W) and water in oil emulsion(W/O) formulations use same dosage UV filters to discuss sun protection factor (SPF)change and enhancement.
In addiction, three kinds of Chinese herbal extracts (HA, HB, HC) be claim for anti-oxidation and anti-free radial functional ability adding in sunscreen lotions; to find SPF value and erythema also melanin change. We are looking forward to find high SPF value and high UVA protection the best composition; also it decrease UV filters dosage at the same time. Labsphere UV1000S be used for SPF evaluation in vitro. Plasmid DNA with H2O2 after UV irradiation causing damage be a model for photo-protection. Multiport model 601-150W be use for Minimal Erythema Dosage (MED) evaluation in vivo. These methods make sure sunscreen lotions for UV protection.
These parameters in vitro test: 3% Parsol MCX, 2% Parsol 1789, 5% pure TiO2 sunscreen lotion get SPF 33.21 for O/W type; get SPF 51.99 for W/O type. On plasmid DNA with H2O2 after UV irradiation causing damage test; SPF 13.2 getting 18.05% protective effect, SPF 33.21 to get 50.89% protective effect. Higher SPF value sunscreen lotions show better photoprotection in UVB wavelength. In vivo test get similar SPF 12 at same dosage UV filters but different (O/W, W/O) type emulsion. Between in vitro and in vivo test; when SPF become higher, distinctively much. Otherwise containing Chinese herbal extracts HA,
HB, HC sunscreen lotions that we observe SPF value and erythema change. In vitro test, O/W type sunscreen lotions get SPF 31.87-42.95; W/O type sunscreen lotions get SPF 33.7-55.61.Chinese herbal extracts 1% HA adds in previous sunscreen lotions; both two types emulsion, we get higher than SPF 14.4 in vivo.
According in vitro and in vivo test results; in vitro test, we know that same dosage UV filters W/O perform better than O/W for SPF value nearly 20, but we can’t find the same result in vivo test. If we trust high SPF protective effect in vitro; we will severely get sunburn after UV irradiation. Plasmid DNA model provide a convenient method for sunscreen products photoprotective evaluation. The result is more closely in vivo test compare with in vitro test.
Chinese herbal extracts 1% HA sunscreen lotion. We can’t find SPF value enhancement in vitro, but it truly delay for erythema appearance also erythema insistence shorter in vivo. When we design sunscreen products formulation: The measurement of diffuse transmittance only a part of reference in vitro ;because it can’t read UV inducing erythema and cell damage. In fact, they are warning for photoaging and skin cancer.
Chinese herbal extract HA serve as natural alternatives for photopro-
tection and dose suitable UV filters that they be use for best sunscreen formulations in future. |
