Young women in sub-Saharan Africa have the highest risk of human immunodeficiency virus (HIV) acquisition through sexual contact of all groups. Vaginal controlled release of antiretrovirals is a priority option for the prevention of sexual transmission of the virus in women. In this manuscript, bilayer films were prepared based on ethylcellulose and a natural polymer (xanthan or tragacanth gum) plasticized with glycerol and tributylcitrate for tenofovir-controlled release. The mechanical properties and microstructure of the blank films were characterized by texture analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy. The loaded films were evaluated in simulated vaginal fluid through release and swelling studies and ex vivo mucoadhesion assessments. The results show that the preparation method produced bilayer films with adequate mechanical properties. The contribution of both layers allowed the sustained release of tenofovir and a mucoadhesion time of up to 360 h. The toxicity of the materials was evaluated in three cell lines of vaginal origin. The films constituted by ethylcellulose and xanthan gum in a 2:1 proportion (EX2-D) showed the longest mucoadhesion time, with 15 days of tenofovir-controlled release, zero toxicity, and optimal mechanical properties. These films are therefore a promising option for offering women a means of self-protection against the sexual transmission of HIV.

中文翻译：

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基于乙基纤维素和生物聚合物的替诺福韦阴道持续释放的阴道粘膜粘附双层膜的开发和体外/体外表征。

通过所有群体的性接触，撒哈拉以南非洲地区的年轻女性感染人类免疫缺陷病毒（HIV）的风险最高。阴道控释抗逆转录病毒药物是预防妇女中性传播病毒的优先选择。在此手稿中，双层薄膜是基于乙基纤维素和天然聚合物（黄原胶或黄aga胶）制备的，该天然聚合物用甘油和柠檬酸三丁酯增塑以替诺福韦控释。通过质构分析，傅立叶变换红外光谱和扫描电子显微镜对空白膜的力学性能和微观结构进行了表征。通过释放和溶胀研究以及离体试验，在模拟的阴道液中评估了加载的膜粘膜粘附评估。结果表明，该制备方法制备出具有足够机械性能的双层薄膜。两层的贡献使替诺福韦持续释放，粘膜粘附时间长达360小时。在三种阴道来源的细胞系中评估了该材料的毒性。由乙基纤维素和黄原胶以2：1的比例（EX2-D）构成的薄膜显示最长的粘膜粘附时间，替诺福韦控制释放15天，零毒性和最佳机械性能。因此，这些电影为妇女提供了一种自我保护的手段，以防止艾滋病毒的性传播，是一个有前途的选择。