Laboratório de Desenvolvimento Galênico (LADEG), Departamento de Medicamentos, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
Nanotechnology. 2017 Feb 10;28(6):065101. doi: 10.1088/1361-6528/28/6/065101. Epub 2017 Jan 10.
Photodynamic therapy (PDT) combines light with photosensitizers (PS) for production of reactive oxygen species (ROS) that can kill infectious microorganisms such as bacteria, fungi and protozoa. The application of nanotechnology has enabled the advancement of PDT because many PS are insoluble in water, necessitating a nanocarrier as a physiologically acceptable carrier. Nanoemulsions are efficient nanocarriers for solubilizing liposoluble drugs, like the PS, in water. Cutaneous (CL) and mucocutaneous leishmaniasis (ML) are caused by different species of the genus Leishmania, transmitted to humans by sandfly bites. Parasites are hosted in skin macrophages producing ulcerative lesions. Thus, a topical treatment, effective and inexpensive, for CL and ML is preferable to systemic interventions. There are topical treatments like paromomycin and amphotericin B, but they have many local side effects or a very high cost, limiting their use. This work aimed to develop a zinc phthalocyanine (photosensitizer) oil-in-water nanoemulsion, essential clove oil and polymeric surfactant (Pluronic F127) for the formulation of a topical delivery system for use in PDT against Leishmania amazonensis and Leishmania infantum. The nanoemulsion was produced by a high-energy method and characterized by size, polydispersity, morphology, pH, content and stability studies. The toxicity in the dark and the photobiological activity of the formulations were evaluated in vitro for Leishmania and macrophages. The formulation presented was pH compatible with topical use, approximately 30 nm in size, with a polydispersity index ≤0.1 and remained stable at room and refrigerator temperature during the stability study (60 days). The zinc phthalocyanine nanoemulsion is effective in PDT against Leishmania spp.; use against skin infections can be a future application of this topical formulation, avoiding the use of oral or injectable medications, decreasing systemic adverse effects.
光动力疗法（PDT）将光与光敏剂（PS）结合使用，产生可以杀死细菌、真菌和原生动物等传染性微生物的活性氧（ROS）。纳米技术的应用使 PDT 得以发展，因为许多 PS 不溶于水，需要纳米载体作为生理上可接受的载体。纳米乳剂是一种有效的纳米载体，可将脂溶性药物（如 PS）溶解在水中。皮肤（CL）和粘膜皮肤利什曼病（ML）是由利什曼属的不同种引起的，由沙蝇叮咬传播给人类。寄生虫存在于皮肤巨噬细胞中，导致溃疡性病变。因此，CL 和 ML 的局部治疗，有效且廉价，优于全身干预。有一些局部治疗方法，如巴龙霉素和两性霉素 B，但它们有许多局部副作用或非常高的成本，限制了它们的使用。本工作旨在开发一种锌酞菁（光敏剂）油包水乳剂，必需的丁香油和聚合物表面活性剂（Pluronic F127），用于配制一种用于 PDT 治疗美洲利什曼原虫和婴儿利什曼原虫的局部递药系统。纳米乳剂通过高能方法制备，并通过粒径、多分散性、形态、pH 值、含量和稳定性研究进行了表征。在黑暗中和体外评估了制剂对利什曼原虫和巨噬细胞的毒性和光生物活性。所提出的制剂的 pH 值与局部使用兼容，粒径约为 30nm，多分散指数≤0.1，在稳定性研究（60 天）期间在室温下和冰箱温度下保持稳定。锌酞菁纳米乳剂在 PDT 中对利什曼原虫有效；该局部制剂的未来应用可能是治疗皮肤感染，避免使用口服或注射药物，减少全身不良反应。
