Burygin G L, Khlebtsov B N, Shantrokha A N, Dykman L A, Bogatyrev V A, Khlebtsov N G
Nanoscale Res Lett. 2009 Apr 21;4(8):794-801. doi: 10.1007/s11671-009-9316-8.
The bacterial action of gentamicin and that of a mixture of gentamicin and 15-nm colloidal-gold particles on Escherichia coli K12 was examined by the agar-well-diffusion method, enumeration of colony-forming units, and turbidimetry. Addition of gentamicin to colloidal gold changed the gold color and extinction spectrum. Within the experimental errors, there were no significant differences in antibacterial activity between pure gentamicin and its mixture with gold nanoparticles (NPs). Atomic absorption spectroscopy showed that upon application of the gentamicin-particle mixture, there were no gold NPs in the zone of bacterial-growth suppression in agar. Yet, free NPs diffused into the agar. These facts are in conflict with the earlier findings indicating an enhancement of the bacterial activity of similar gentamicin-gold nanoparticle mixtures. The possible causes for these discrepancies are discussed, and the suggestion is made that a necessary condition for enhancement of antibacterial activity is the preparation of stable conjugates of NPs coated with the antibiotic molecules.
采用琼脂孔扩散法、菌落形成单位计数法和比浊法，研究了庆大霉素以及庆大霉素与15纳米胶体金颗粒混合物对大肠杆菌K12的细菌作用。向胶体金中添加庆大霉素会改变金的颜色和消光光谱。在实验误差范围内，纯庆大霉素及其与金纳米颗粒（NPs）的混合物之间的抗菌活性没有显著差异。原子吸收光谱表明，在应用庆大霉素-颗粒混合物后，琼脂中细菌生长抑制区域没有金纳米颗粒。然而，游离的纳米颗粒扩散到了琼脂中。这些事实与早期表明类似庆大霉素-金纳米颗粒混合物细菌活性增强的研究结果相矛盾。讨论了这些差异的可能原因，并提出增强抗菌活性的一个必要条件是制备包被有抗生素分子的纳米颗粒稳定缀合物。
