National University of Singapore – Page 2

Gels of Carbon Nanotubes and Nonionic Surfactant and High-quality Carbon Nanotube Films Prepared by Gel Coating

Ouyang J., National University of Singapore, SG

Processing of large-scale carbon nanotubes (CNTs) are very important for the application of CNTs in various aspects. Here, we report CNT gels by dispersing CNTs in various nonionic surfactants. High-quality CNT films were prepared by [...]

Immobilization of Enzymes on Functionalized Magnetic Nanoparticles for Efficient Biocatalysis

Li Z., Wang D.I.C., Wang W., National University of Singapore, SG

In this paper, iron oxide magnetic nanoparticles were synthesized by co-precipitation method and were functionalized with aldehyde group. Spherical superparamagnetic nanoparticles with diameter of 100 nm were obtained based on the results of field emission [...]

Upconverting nanoparticles for in vitro and in vivo cellular imaging

Chatterjee D.K., Zhang Y., National University of Singapore, SG

Conventional fluorescent labels are of limited in vivo utility because short-wavelength radiation penetrates tissues poorly and excites strong background autofluorescence. Upconversion nanoparticles (UCN) convert low-energy exciting photons to visible emissions, resulting in deep tissue penetration [...]

Upconverting nanoparticles for photodynamic therapy

Chatterjee D.K., Zhang Y., National University of Singapore, SG

Photodynamic therapy involves killing of diseased cells by excitation of photosensitizer chemicals with high energy light to produce cytotoxic oxygen species from surrounding dissolved oxygen. However, poor tissue penetration of high energy light and hydrophobic [...]

Directed Growth of Carbon Nanotubes Utilizing Plasma Induced Surface Charging Voltage

Koo C.K., Law J.B.K., Thong J.T.L., National University of Singapore, SG

In this work, we present a method for directed lateral growth of CNTs between electrodes on a substrate during an in-situ CNT growth process, by utilizing plasma induced charging inherent in a Radio Frequency (RF) [...]

Facile Assembly of Nanoparticles into 2D Micro-structured Films by a Polymer-aided Self-organization Process

Ajikumar P.K., Nurmawati M.H., Renu R., Valiyaveettil S., National University of Singapore, SG

There have been many reported approaches for tailoring the properties of nanomaterials by manipulating the way in which they order on several different length scales. The self-assembly of micro- and nano-structures in periodic arrangement of [...]

A Novel Biodegradable System Based on BSA/PCL Core-shell Structured Nanofibers for Controlled Drug Delivery

Feng Y., Ramakrishna S., Yong T., Zhang Y.Z., National University of Singapore, SG

Electrospun core-shell structured nanofibers encapsulating BSA were explored as a potential drug delivery model in a biological system in present study. These nanofibers were prepared by coaxial electrospinning method with poly (caprolactone) (PCL) as the [...]

Nanoengineered Encapsulation of Organic Microcrystal as Novel Biolabels

Cheung K.Y., Mak W.C., Renneberg R., Trau D., National University of Singapore, SG

Here we report on our latest developments for nanoengineered encapsulation and surface design of micro and submicron crystals for biochemcial assay. Improvement has been made by decreasing the size of the organic crystals to submicrometer [...]

Carbon Nanotube-based Labels for Sensitive Nucleic Acids Detection

Heng C.K., Lee A.C., Lim T.M., Poenar D., Sheu F.S., Tan S.N., Ye J.S., National University of Singapore, SG

A novel multiple-labelled conjugate with carbon nanotubes (CNTs) to amplify hybridization signal was developed to improve the nucleic acids assay sensitivity. The carboxylated CNTs were functionalized by horseradish peroxidase (HRP) and single-stranded oligonucleotides via diimide-activated [...]

ZnO Nanoparticles Beaded Multiwalled Carbon Nanotubes

Elim H.I., Foo Y.L., Ji W., Quek W.T., Sow C.H., Thong J., Triparthy S., Zhu Y., National University of Singapore, SG

In this work, we report a hybrid system of ZnO nanoparticles on MWNT scaffolds synthesized via a very simple and straightforward process. This involved the coating of pure Zn on as-grown aligned MWNT films, followed [...]