Alarcon Romina, Walter Mariana, Paez Maritza, Azócar Manuel Ignacio
Departamento de Quimica de los Materiales, Facultad de Quimica y Biologia, & SMAT-C, Universidad de Santiago de Chile, Av. Bernardo O'Higgins 3363, Estacion Central, Santiago 8990000, Chile.
Nanomaterials (Basel). 2023 Jan 20;13(3):428. doi: 10.3390/nano13030428.
Silver nanoparticles (AgNPs) have been extensively studied during recent decades as antimicrobial agents. However, their stability and antibacterial activity over time have yet to be sufficiently studied. In this work, AgNPs were coated with different stabilizers (naproxen and diclofenac and 5-chlorosalicylic acid) in different concentrations. The suspensions of nanostructures were characterized by transmission electron microscopy, UV-Vis and FT-IR spectroscopic techniques. The antibacterial activity as a function of time was determined through microbiological studies against . The AgNPs show differences in stabilities when changing the coating agent and its concentration. This fact could be a consequence of the difference in the nature of the interaction between the stabilizer and the surface of the NPs, which were evaluated by FT-IR spectroscopy. In addition, an increase in the size of the nanoparticles was observed after 30 days, which could be related to an Ostwald maturation phenomenon. This result raises new questions about the role that stabilizers play on the surface of NPs, promoting size change in NPs. It is highly probable that the stabilizer functions as a growth controller of the NPs, thus determining an effect on their biological properties. Finally, the antibacterial activity was evaluated over time against the bacterium Staphylococcus aureus. The results showed that the protective or stabilizing agents can play an important role in the antibacterial capacity, the control of the size of the AgNPs and additionally in the stability over time.
近几十年来，银纳米颗粒（AgNPs）作为抗菌剂受到了广泛研究。然而，它们随时间的稳定性和抗菌活性尚未得到充分研究。在这项工作中，AgNPs用不同浓度的不同稳定剂（萘普生、双氯芬酸和5-氯水杨酸）进行了包覆。通过透射电子显微镜、紫外-可见光谱和傅里叶变换红外光谱技术对纳米结构的悬浮液进行了表征。通过针对……的微生物学研究确定了作为时间函数的抗菌活性。当改变包覆剂及其浓度时，AgNPs的稳定性表现出差异。这一事实可能是由于稳定剂与纳米颗粒表面之间相互作用性质的差异导致的，这通过傅里叶变换红外光谱进行了评估。此外，30天后观察到纳米颗粒尺寸增大，这可能与奥斯特瓦尔德熟化现象有关。这一结果引发了关于稳定剂在纳米颗粒表面所起作用的新问题，即促进纳米颗粒尺寸变化。很可能稳定剂起到了纳米颗粒生长控制剂的作用，从而对其生物学性质产生影响。最后，对金黄色葡萄球菌随时间的抗菌活性进行了评估。结果表明，保护剂或稳定剂在抗菌能力、AgNPs尺寸控制以及随时间的稳定性方面都能发挥重要作用。
