Departamento de Química Inorgánica and Instituto de Biotecnología, Universidad de Granada, 18071 Granada, Spain.
Departamento Ciencia de Materiales e Ingeniería Metalúrgica y Química Inorgánica, Universidad de Cádiz, 11510 Cádiz, Spain.
Nanoscale. 2022 Apr 14;14(15):5716-5724. doi: 10.1039/d1nr08513a.
Probiotic bacteria were used as carriers of metallic nanoparticles to develop innovative oral agents for hyperthermia cancer therapy. Two synthetic strategies were used to produce the different therapeutic agents. First, the probiotic bacterium was simultaneously loaded with magnetic (MNPs) and gold nanoparticles (AuNPs) of different morphologies to produce AuNP + MNP-bacteria systems with both types of nanoparticles arranged in the same layer of bacterial exopolysaccharides (EPS). In the second approach, the probiotic was first loaded with AuNP to form AuNP-bacteria and subsequently loaded with MNP-EPS to yield AuNP-bacteria-EPS-MNP with the MNP and AuNP arranged in two different EPS layers. This second strategy has never been reported and exploits the presence of EPS-EPS recognition which allows the layer-by-layer formation of structures on the bacteria external wall. The AuNP + MNP-bacteria and AuNP-bacteria-EPS-MNP samples were characterized by scanning (SEM) and transmission electron microscopy (TEM), and UV-vis spectroscopy. The potential of these two heterobimetallic systems as magnetic hyperthermia or photothermal therapy agents was assessed, validating their capacity to produce heat either during exposure to an alternating magnetic field or near-infrared laser light. The probiotic has already been proposed as an oral drug carrier, able to overcome the stomach medium and deliver drugs to the intestines, and it is actually marketed as an oral supplement to reinforce the gut microbiota, thus, our results open the way for the development of novel therapeutic strategies using these new heterobimetallic AuNP/MNP-bacteria systems in the frame of gastric diseases, using them, for example, as oral agents for cancer treatment with magnetic hyperthermia and photothermal therapy.
益生菌被用作金属纳米粒子的载体，开发用于癌症热疗的创新口服制剂。采用两种合成策略来制备不同的治疗剂。首先，益生菌同时负载磁性（MNPs）和不同形态的金纳米粒子（AuNPs），以产生具有两种类型纳米粒子排列在同一细菌胞外多糖（EPS）层中的 AuNP+MNP-细菌系统。在第二种方法中，益生菌首先负载 AuNP 形成 AuNP-细菌，然后负载 MNP-EPS 以产生 AuNP-细菌-EPS-MNP，其中 MNP 和 AuNP 排列在两个不同的 EPS 层中。这种第二种策略从未有过报道，利用了 EPS-EPS 识别的存在，这允许在细菌外壁上逐层形成结构。通过扫描电子显微镜（SEM）和透射电子显微镜（TEM）以及紫外可见光谱对 AuNP+MNP-细菌和 AuNP-细菌-EPS-MNP 样品进行了表征。评估了这两种异金属双组分系统作为磁热疗或光热疗剂的潜力，验证了它们在暴露于交变磁场或近红外激光光下产生热量的能力。益生菌已被提议作为口服药物载体，能够克服胃介质并将药物递送到肠道，并且实际上作为口服补充剂出售以增强肠道微生物群，因此，我们的结果为开发新型治疗策略开辟了道路使用这些新型异金属 AuNP/MNP-细菌系统在胃病框架内，例如将其用作磁热疗和光热疗的口服癌症治疗剂。
