Chakraborti Soumyananda, Mandal Amit Kumar, Sarwar Shamila, Singh Prashantee, Chakraborty Ranadhir, Chakrabarti Pinak
Department of Biochemistry, Bose Institute, P1/12 CIT Scheme VIIM, Kolkata 700054, India.
Omics Laboratory, Department of Biotechnology, University of North Bengal, Siliguri 734013, West Bengal, India.
Colloids Surf B Biointerfaces. 2014 Sep 1;121:44-53. doi: 10.1016/j.colsurfb.2014.03.044. Epub 2014 May 22.
Zinc oxide nanoparticles (ZnO-NP) were synthesized by alcoholic route using zinc acetate as the precursor material and lithium hydroxide as hydrolyzing agent. Further ZnO-PEI NP (derivative of ZnO-NP) was made in aqueous medium using the capping agent polyethyleneimine (PEI). The nanoparticles were characterized by XRD measurements, TEM and other techniques; the weight % of coating shell in the polymer-capped particles was determined by TGA. ZnO-PEI NP is more soluble in water than the uncapped ZnO-NP, and forms a colloidal suspension in water. PEI-capped ZnO-NP exhibited better antibacterial activity when compared with that of uncapped ZnO-NP against a range of multiple-antibiotic-resistant (MAR) Gram-negative bacterial strains harboring genes of high-pathogenicity island. ZnO-NP effectively killed these microorganisms by generating reactive oxygen species (ROS) and damaging bacterial membrane. ZnO-PEI NP at LD50 dose in combination with tetracycline showed synergistic effect to inhibit tetracycline-resistant Escherichia coli MREC33 growth by 80%. These results open up a new vista in therapeutics to use antibiotics (which have otherwise been rendered useless against MAR bacteria) in combination with minimized dosage of nanoparticles for the more effective control of MAR pathogenic bacteria.
采用乙醇法，以醋酸锌为前驱体材料、氢氧化锂为水解剂合成了氧化锌纳米颗粒（ZnO-NP）。进一步地，在水相中使用封端剂聚乙烯亚胺（PEI）制备了ZnO-PEI NP（ZnO-NP的衍生物）。通过X射线衍射测量、透射电子显微镜及其他技术对纳米颗粒进行了表征；通过热重分析测定了聚合物包覆颗粒中包覆壳的重量百分比。ZnO-PEI NP在水中的溶解度比未包覆的ZnO-NP更高，并在水中形成胶体悬浮液。与未包覆的ZnO-NP相比，PEI包覆的ZnO-NP对一系列携带高致病性岛基因的多重耐药（MAR）革兰氏阴性菌表现出更好的抗菌活性。ZnO-NP通过产生活性氧（ROS）并破坏细菌膜有效地杀死了这些微生物。ZnO-PEI NP在半数致死剂量下与四环素联合使用时，显示出协同作用，可抑制耐四环素大肠杆菌MREC33的生长达80%。这些结果为治疗学开辟了一个新的前景，即使用抗生素（否则对MAR细菌无效）与最小剂量的纳米颗粒联合使用，以更有效地控制MAR病原菌。
