The current study aimed to deliver minoxidil (2,4-diamino-6-piperidinopyrimidine 3-oxide; MXD), a potent hypertrichotic agent, into the pilosebaceous units, exploring the potential of the liposomal system. MXD-loaded liposomes of different compositions were prepared by a thin-film hydration technique and subsequently characterized for various vesicle-specific attributes (i.e., size, shape, lamellarity, and entrapment efficiency). Comparative analysis among these compositions was conducted with reference to their vesicle-specific parameters, drug deposition, and drug-delivery mechanism toward pilosebaceous units. The latter may bring about a distinct change in MXD therapy for various ailments related to pilosebaceous units, such as alopecia. The in vitro drug release, ex vivo skin permeation, and drug-retention behavior of the prepared formulation were evaluated by employing rat skin (normal as well as pilosebaceous free) and semipermeable membrane. The results revealed that the neutral liposomes (mean vesicle size, 3.83 +/- 0.18 microm) showed maximum drug deposition in the pilosebaceous units among all the other tested formulations. A quantitative estimation of pilosebaceous delivery revealed that the concentration of MXD in each pilosebaceous unit decreased in the following order: neutral liposomal formulation (5.8 x 10(3) to 7.25 x 10(3) microg) > positively charged liposomal formulation (4.7 x 10(3) to 5.87 x 10(3) microg) > negatively charged liposomal formulation (4.2 x 10(3) to 5.25 x 10(3) microg) > nonliposomal formulation (1.6 x 10(3) to 2.0 x 10(3) microg). Stability studies construed the need to store the liposomal formulation at lower temperatures. The results of the current work indicate that the neutral liposomes can deliver the drug molecules into pilosebaceous units more effectively than the other studied formulations.

中文翻译：

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用于输送至毛囊皮脂单位的米诺地尔脂质体系统的开发和表征

目前的研究旨在将米诺地尔（2,4-diamino-6-piperidinopyrimidine 3-oxide; MXD）这种强效多毛剂输送到毛囊皮脂单位，探索脂质体系统的潜力。通过薄膜水合技术制备了不同成分的 MXD 负载脂质体，随后表征了各种囊泡特异性属性（即大小、形状、层状和包封效率）。参考它们的囊泡特异性参数、药物沉积和向毛囊皮脂单位的药物递送机制，对这些组合物进行了比较分析。后者可能会导致 MXD 治疗与毛囊皮脂腺单位相关的各种疾病（例如脱发）发生明显变化。体外药物释放、离体皮肤渗透、通过使用大鼠皮肤（正常以及无毛囊皮脂腺）和半透膜来评估所制备制剂的药物保留行为和药物保留行为。结果显示中性脂质体（平均囊泡大小，3.83 +/- 0.18 microm） 在所有其他测试配方中的毛囊皮脂腺单位中表现出最大的药物沉积。对毛囊皮脂腺递送的定量估计表明，每个毛囊皮脂单位中 MXD 的浓度按以下顺序降低：中性脂质体制剂（5.8 x 10(3) 至 7.25 x 10(3) 微克）> 带正电荷的脂质体制剂（4.7 x 10 (3) 至 5.87 x 10(3) 微克) > 带负电荷的脂质体制剂 (4.2 x 10(3) 至 5.25 x 10(3) 微克) > 非脂质体制剂 (1.6 x 10(3) 至 2.0 x 10(3)微克）。稳定性研究表明需要在较低温度下储存脂质体制剂。当前工作的结果表明，中性脂质体可以比其他研究的制剂更有效地将药物分子输送到毛囊皮脂单位。