微生物传感器网络中载物对革兰氏阳性和阴性细菌生物膜的影响
Impact of the antibiotic-cargo from MSNs on Gram-positive and Gram-negative bacterial biofilms
摘要：
介孔二氧化硅纳米颗粒是一种很有前途的用于感染治疗的药物纳米载体。许多研究都集中在评估MSN封装抗生素并以受控方式释放它们的能力。然而，很少有人关注确定从这些纳米系统释放的抗生素剂量，这些纳米系统在整个释放时间内对生物膜有效。在此，我们报告了一个系统的和定量的研究，从MSN上的革兰氏阳性和革兰氏阴性细菌生物膜释放的寄生虫货物的直接影响。将左氧氟沙星（LVX）、庆大霉素（GM）和利福平（RIF）分别负载于纯硅胶和氨基修饰的MSNs中。这解释了这些纳米系统的多功能性，因为它们能够装载和释放不同化学性质的不同抗生素分子。测定两种细菌菌株释放的抗生素的生物活性曲线，其允许计算对细菌生物膜有效的活性剂量。此外，在体外生物相容性测定成骨样细胞进行了在不同的时间段。尽管在非常初始的阶段观察到细胞活力的轻微降低，但由于初始爆发的抗生素释放，这些纳米系统的生物相容性得到证明，因为在72小时的测定后实现了细胞活力的恢复。从MSN释放的GM的生物活性曲线显示持续的模式和2-6 μg/mL范围内的抗生素剂量长达100 h，这不足以根除生物膜。在LVX和RIF的情况下，观察到一级动力学，其特征在于初始突释效应，然后在MIC以上持续释放长达96小时。这样的剂量减少了99.9%的细菌生物膜，并保持活性长达72小时，没有出现细菌耐药性。
英文摘要：
Mesoporous silica nanoparticles (MSNs) are promising drug nanocarriers for infection treatment. Many investigations have focused on evaluating the capacity of MSNs to encapsulate antibiotics and release them in a controlled fashion. However, little attention has been paid to determine the antibiotic doses released from these nanosystems that are effective against biofilm during the entire release time. Herein, we report a systematic and quantitative study of the direct effect of the antibiotic-cargo released from MSNs on Gram-positive and Gram-negative bacterial biofilms. Levofloxacin (LVX), gentamicin (GM) and rifampin (RIF) were separately loaded into pure-silica and amino-modified MSNs. This accounts for the versatility of these nanosystems since they were able to load and release different antibiotic molecules of diverse chemical nature. Biological activity curves of the released antibiotic were determined for both bacterial strains, which allowed to calculate the active doses that are effective against bacterial biofilms. Furthermore, in vitro biocompatibility assays on osteoblast-like cells were carried out at different periods of times. Albeit a slight decrease in cell viability was observed at the very initial stage, due to the initial burst antibiotic release, the biocompatibility of these nanosystems is evidenced since a recovery of cell viability was achieved after 72 h of assay. Biological activity curves for GM released from MSNs exhibited sustained patterns and antibiotic doses in the 2-6 μg/mL range up to 100 h, which were not enough to eradicate biofilm. In the case of LVX and RIF first-order kinetics featuring an initial burst effect followed by a sustained release above the MIC up to 96 h were observed. Such doses reduced by 99.9% bacterial biofilm and remained active up to 72 h with no emergence of bacterial resistance.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
