Multi-functional Advanced Nanomaterials for Medicine, Environment and Energy Technologies are topics for doing fundamental and application-oriented research projects at the NEB research group. Advanced nanostructures and nanotechnological engineering are key factors for producing new innovations & international recognized quality. The NEB research group is focusing on advanced nanomaterials, nanohybrids, nanocomposites and their applications to energy and biomedical industry.
Research at NEB is based on interdisciplinary approach by covering advanced materials science, nanoscience and nanotechnology for improving technological innovation and product quality. The researchers at NEB consist of domestic research scientists and international collaborators with expertise in the different fields, our manpower will maintain our position as one of the leading research group in the field of nano-energy and nano-biomedicine.
Core values at NEB are Creativity + Passion and Trust + Harmony
Graphene oxide/silver nanohybrids as multi-functional material for highly efficient bacterial disinfection and detection of organic dye
Le Thi Tam, Ngo Xuan Dinh, Nguyen Van Quy, Tran Quang Huy, Duc-The Ngo, Kristian Mølhave, Anh-Tuan Le
In this work, a multi-functional hybrid system consisting of graphene oxide and silver nanoparticles (GO-Ag NPs) was successfully synthesized by using a two-step chemical process. We firstly demonstrated noticeable bactericidal ability of the GO-Ag hybrid system. We provide more chemo-physical evidence explaining the antibacterial behavior of GO-Ag nanohybrid against Gram-negative Escherichia Coli and Gram-positive Staphylococcus aureus in light of ultrastructural damage analyses and Ag1+ ions release rate onto the cells/medium. A further understanding of the mode of antimicrobial action is very important for designing and developing advanced antimicrobial systems. Secondly, we have also demonstrated that the GO-Ag nanohybrid material could be used as a potential surface enhanced Raman scattering (SERS) substrate to detect and quantify organic dyes, e.g., methylene blue (MB), in aqueous media. Our findings revealed that the GO-Ag hybrid system showed better SERS performance of MB detection than that of pure Ag-NPs. MB could be detected at a concentration as low as 1 ppm. The GO-Ag-based SERS platform can be effectively used to detect trace concentrations of various types of organic dyes in aqueous media. With the aforementioned properties, the GO-Ag hybrid system is found to be very promising as a multi-functional material for advanced biomedicine and environmental monitoring applications.
This paper presents a facile, and ecofriendly method to prepare colloidal silver nanoparticles (AgNPs) at room temperature using bulk silver bars, bi-distilled water, trisodium citrate, and a direct-current voltage source. AgNP formation was confirmed and characterized by ultraviolet–visible spectroscopy, transmission electron microscopy and X-ray diffraction. Their antibacterial activity was examined by disc diffusion and minimum inhibitory concentration (MIC) techniques against three bacterial strains, including the Gram-positive bacteria Staphylococcus aureus and the Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa. Results showed that the size of AgNPs formed was about 19.7±4.3 nm with nearly spherical shape and high purity. The antibacterial activity of as-prepared AgNPs was determined through zones of inhibition against the growth of three bacterial strains on agar. MIC analysis showed that S. aureus had resistance to AgNPs that was about 2–3 times higher than those of E. coli and P. aeruginosa, and that resistance ability depended on the bacterial concentrations inoculated. This work revealed the effective method of synthesizing a large quantity of colloidal AgNPs with high antibacterial effectiveness and potential application in different fields.