Mureed Shumaila, Naz Sadia, Haider Ali, Raza Ali, Ul-Hamid Anwar, Haider Junaid, Ikram Muhammad, Ghaffar Rabia, Irshad Muneeb, Ghaffar Abdul, Saeed Aamer
Solar Cell Applications Research Lab, Department of Physics, Government College University Lahore, Lahore, 54000, Punjab, Pakistan.
Department of Physics, Government College University Lahore, Lahore, 54000, Punjab, Pakistan.
Nanoscale Res Lett. 2021 May 22;16(1):91. doi: 10.1186/s11671-021-03547-6.
The present study is concerned with evaluating the influence of various concentrations of Ag within Cu:Ag bimetallic nanoparticles developed for use as a promising anti-bacterial agent against antibiotic-resistant bacteria. Here, Cu:Ag bimetallic nanoparticles with various concentration ratios (2.5, 5.0, 7.5, and 10 wt%) of Ag in fixed amount of Cu labeled as 1:0.025, 1:0.050, 1:0.075, and 1:0.1 were synthesized using co-precipitation method with ammonium hydroxide and deionized water as solvent, polyvinyl pyrrolidone as a capping agent, and sodium borohydride and ascorbic acid as reducing agents. These formulated products were characterized through a variety of techniques. XRD confirmed phase purity and detected the presence of distinct fcc structures belonging to Cu and Ag phases. FTIR spectroscopy confirmed the presence of vibrational modes corresponding to various functional groups and recorded characteristic peak emanating from the bimetallic. UV-visible spectroscopy revealed reduction in band gap with increasing Ag content. SEM and HR-TEM micrographs revealed spherical morphology of Ag-doped Cu bimetallic with small and large scale agglomerations. The samples exhibited varying dimensions and interlayer spacing. Bactericidal action of synthesized Cu:Ag bimetallic NPs depicted statistically significant (P < 0.05) inhibition zones recorded for various concentrations of Ag dopant against Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and Acinetobacter baumannii (A. baumannii) ranging from (0.85-2.8 mm), (0.55-1.95 mm) and (0.65-1.85 mm), respectively. Broadly, Cu:Ag bimetallic NPs were found to be more potent against gram-positive compared with gram-negative. Molecular docking study of Ag-Cu bimetallic NPs was performed against β-lactamase which is a key enzyme of cell wall biosynthetic pathway from both S. aureus (Binding score: - 4.981 kcal/mol) and A. bauminnii (Binding score: - 4.013 kcal/mol). Similarly, binding interaction analysis against FabI belonging to fatty acid biosynthetic pathway from A. bauminnii (Binding score: - 3.385 kcal/mol) and S. aureus (Binding score: - 3.012 kcal/mol) along with FabH from E. coli (Binding score: - 4.372 kcal/mol) was undertaken. These theoretical computations indicate Cu-Ag bimetallic NPs as possible inhibitor of selected enzymes. It is suggested that exploring in vitro inhibition potential of these materials may open new avenues for antibiotic discovery.
本研究旨在评估不同浓度的银在铜银双金属纳米颗粒中的影响，该双金属纳米颗粒被开发用作一种有望对抗抗生素耐药菌的抗菌剂。在此，使用共沉淀法合成了银在固定量铜中具有不同浓度比（2.5、5.0、7.5和10 wt%）的铜银双金属纳米颗粒，标记为1:0.025、1:0.050、1:0.075和1:0.1，以氢氧化铵和去离子水为溶剂，聚乙烯吡咯烷酮为封端剂，硼氢化钠和抗坏血酸为还原剂。通过多种技术对这些配制产品进行了表征。X射线衍射（XRD）证实了相纯度，并检测到属于铜相和银相的不同面心立方结构的存在。傅里叶变换红外光谱（FTIR）证实了对应于各种官能团的振动模式的存在，并记录了双金属产生的特征峰。紫外可见光谱显示随着银含量的增加带隙减小。扫描电子显微镜（SEM）和高分辨率透射电子显微镜（HR-TEM）显微照片显示了掺银铜双金属的球形形态，有小规模和大规模的团聚。样品表现出不同的尺寸和层间距。合成的铜银双金属纳米颗粒对金黄色葡萄球菌、大肠杆菌和鲍曼不动杆菌的杀菌作用显示，不同浓度银掺杂剂的抑菌圈在统计学上具有显著意义（P < 0.05），范围分别为（0.85 - 2.8毫米）、（0.55 - 1.95毫米）和（0.65 - 1.85毫米）。总体而言，发现铜银双金属纳米颗粒对革兰氏阳性菌的作用比对革兰氏阴性菌更强。对银铜双金属纳米颗粒进行了针对β-内酰胺酶的分子对接研究，β-内酰胺酶是金黄色葡萄球菌（结合分数：-4.981千卡/摩尔）和鲍曼不动杆菌（结合分数：-4.013千卡/摩尔）细胞壁生物合成途径的关键酶。同样，对来自鲍曼不动杆菌（结合分数：-3.385千卡/摩尔）和金黄色葡萄球菌（结合分数：-3.012千卡/摩尔）的脂肪酸生物合成途径中的FabI以及来自大肠杆菌的FabH（结合分数：-4.372千卡/摩尔）进行了结合相互作用分析。这些理论计算表明铜银双金属纳米颗粒可能是所选酶的抑制剂。建议探索这些材料的体外抑制潜力可能为抗生素发现开辟新途径。
