In vivo EPR of topical delivery of a hydrophilic substance encapsulated in multilamellar liposomes applied to the skin of hairless and normal mice.
In vivo EPR of topical delivery of a hydrophilic substance encapsulated in multilamellar liposomes applied to the skin of hairless and normal mice.
复制标题
体内 EPR 将封装在多层脂质体中的亲水物质局部递送至无毛小鼠和正常小鼠的皮肤。
DOI：
10.1016/s0168-3659(99)00272-2
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
Swartz,HM
中科院分区：
文献类型：
--
作者：
Honzak,L;Sentjurc,M;Swartz,HM
在体内低频EPR被用来测量通过使用多层脂质体的亲水性物质的局部递送的增强。使用无毛小鼠和正常小鼠研究了经表皮或/和transfollicular转运途径的贡献。使用先前已显示对离体皮肤具有不同增强性质的两种脂质体分散体。测量了包封在脂质体中的应用于皮肤的亲水性自旋探针GluSL（N-（1-氧基-2，2，6，6-四甲基-4-哌啶基）-2，3，4，5，6-五羟基-己酰胺）的还原动力学。为了区分皮肤表面GluSL的还原与皮肤内部GluSL的还原，使用了氧化剂铁氰化钾（KFeCN）。这不会渗透到皮肤中，因此它只在皮肤表面将羟胺氧化回氮氧化物。我们观察到这两种类型的脂质体的性质的显着差异，就其与皮肤接触时的稳定性和它们的运输特性。体内测量的结果与离体获得的结果一致，表明体内L-带EPR是一种强大的技术，用于在活体动物皮肤中的药代动力学。结果还表明，在我们的实验期间（通常约60分钟），血流清除和动物处死后皮肤的可能变化不影响脂质体包封物质渗透到皮肤中的结果。无毛小鼠皮肤中GluSL的减少与正常小鼠相似，表明在该实验模型中，跨毛囊渗透在体内并不重要。
In vivo low frequency EPR was used to measure the enhancement of topical delivery of hydrophilic substances by use of multilamellar liposomes. The contribution of transepidermal or/and transfollicular routes of transport was investigated using hairless and normal mice. Two liposome dispersions that previously had been shown to have different enhancement properties on ex vivo skin were used. The kinetics of the reduction of hydrophilic spin probe GluSL (N-(1-oxyl-2,2,6,6-tetramethyl-4-piperidinyl)-2,3,4,5,6-pentahydroxy-hexaneamide) applied to the skin encapsulated into the liposomes was measured. To distinguish the reduction of GluSL on the skin surface from its reduction inside the skin, the oxidizing agent potassium ferricyanide (KFeCN) was used. This does not penetrate into the skin and therefore it oxidizes hydroxylamines back to nitroxide only on the surface of the skin. We observed significant differences in the properties of the two types of liposomes with respect to their stability when in contact with skin and their transport characteristics. The results measured in vivo are consistent with those obtained ex vivo, indicating that in vivo L-band EPR is a powerful technique for following pharmacokinetics in the skin of live animals. The results also show that clearance by blood flow and possible alterations of skin after sacrifice of animal do not influence the results of penetration of liposome entrapped substances into the skin during the time of our experiment (typically around 60 min). The reduction of GluSL in the skin of hairless vs. normal mice was similar, indicating that the transfollicular penetration was not of major importance in vivo in this experimental model.