Bacterial resistance has become an important public health problem. Bacteria have been acquiring mechanisms to resist the action of antimicrobial active pharmaceutical ingredients (API). Based on this, a promising alternative is the use of nanotechnology, since when the systems are presented in nanometric size, there is an increase in the interaction and concentration of the action at the target site improving the activity. Thus, this study aims to develop a polymeric nanoparticle (PN) composed of chitosan and hydroxypropylmethylcellulose, as an innovative strategy for the administration of an association between ceftriaxone and extract of S. brasiliensis, for the treatment of Enterobacteriaceae. From a Box–Behnken design, nanoparticles were obtained and evaluated using the DLS technique, obtaining the particle size between 440 and 1660 nm, IPD from 0.42 to 0.92, and positive charges. Morphological characteristics of PN by SEM revealed spherical morphology and sizes similar to DLS. Infrared spectroscopy showed no chemical interaction between the components of the formulation. The broth microdilution technique evaluated their antimicrobial activity, and a considerable improvement in the activity of the extract and the API compared to the free compounds was found, reaching an improvement of 133 times in the minimum inhibitory activity CRO.

中文翻译：

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与头孢曲松钠和巴西多孢菌提取物对多耐药肠杆菌的聚合纳米颗粒。

细菌耐药性已成为重要的公共卫生问题。细菌已经获得了抵抗抗菌活性药物成分（API）作用的机制。基于此，一种有前途的替代方法是使用纳米技术，因为当系统以纳米尺寸显示时，在靶位点的相互作用和作用浓度都有所提高，从而改善了活性。因此，本研究旨在开发一种由壳聚糖和羟丙基甲基纤维素组成的聚合物纳米颗粒（PN），作为头孢曲松与巴西链球菌提取物之间缔合的一种创新策略。，用于治疗肠杆菌科。通过Box–Behnken设计，使用DLS技术获得并评估了纳米颗粒，获得了440至1660 nm的粒径，0.42至0.92的IPD和正电荷。SEM的PN的形态学特征显示出球形形态和大小类似于DLS。红外光谱显示制剂的组分之间没有化学相互作用。肉汤微稀释技术评估了它们的抗菌活性，与游离化合物相比，提取物和API的活性得到了显着改善，最小抑制活性CRO达到了133倍。