Abstract Photoprotective nanoemulsions are able to attenuate skin damage from overexposure to the sun, thus avoiding the immediate effects caused by ultraviolet radiation. The global cosmetics market understands that there is a demand and greater acceptance by consumers for formulations containing natural products compatible with the skin. Consequently, there is an increasingly need to develop such products that are safe and effective. Furthermore, there is a growing interest in nanoemulsions (NE) in the pharmaceutical industry, due the versatility of incorporating lipophilic substances into cosmetic formulations. In the present work, oil-in-water photoprotective nanoemulsions containing microbial carotenoids, buriti oil and chemical filters were developed and characterized. The essential physical properties of the droplets, the transmission electronic microscopy (TEM), the sun protection factor (SPF) as well as the stability of the formulations were determined. In vitro phototoxicity was evaluated using Balb 3 T3 with relative cell viability estimated by Neutral Red Uptake, with the Photo Irritation Factor (PIF) and the Medium Photo Effect Factor (MPF) as the measurement parameters. Nanoemulsion 3 (NE3) showed spherical morphology with an average droplet size of 142.11 ± 0.92 nm and polydispersity index (PDI) of 0.198 ± 0.017. This nanoemulsion containing microbial carotenoids and buriti oil exhibited a SPF of 36 ± 1.5. Neutral Red Uptake revealed that the cells kept their viability even after irradiation and those nanoemulsions containing the microbial carotenoids and buriti oil were not phototoxic. The addition of microbial carotenoids and buriti oil in nanoemulsions was positive in increasing the mean SPF values compared to the control formulation.

中文翻译：

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含有微生物类胡萝卜素和buriti油的光保护纳米乳剂：功效和安全性研究

摘要 光保护纳米乳液能够减轻过度暴露在阳光下的皮肤损伤，从而避免紫外线辐射引起的直接影响。全球化妆品市场明白，消费者对含有与皮肤相容的天然产品的配方有需求，并且越来越接受。因此，越来越需要开发这样的安全有效的产品。此外，由于在化妆品配方中加入亲脂性物质的多功能性，制药行业对纳米乳剂 (NE) 的兴趣越来越大。在目前的工作中，开发并表征了含有微生物类胡萝卜素、buriti 油和化学过滤器的水包油光保护纳米乳液。液滴的基本物理性质，测定了透射电子显微镜 (TEM)、防晒系数 (SPF) 以及配方的稳定性。使用 Balb 3 T3 评估体外光毒性，通过中性红摄取估计相对细胞活力，以光刺激因子 (PIF) 和中等光效应因子 (MPF) 作为测量参数。纳米乳液 3 (NE3) 呈球形，平均液滴尺寸为 142.11 ± 0.92 nm，多分散指数 (PDI) 为 0.198 ± 0.017。这种含有微生物类胡萝卜素和buriti油的纳米乳剂的SPF值为36±1.5。Neutral Red Uptake 表明细胞即使在辐照后仍能保持活力，并且那些含有微生物类胡萝卜素和 buriti 油的纳米乳剂没有光毒性。