%0 Journal Article
%T Fluorescent Silica Nanoparticles in the Detection and Control of the Growth of Pathogen
%A Kethirabalan Chitra
%A Gurusamy Annadurai
%J Journal of Nanotechnology
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/509628
%X In this present study the bioconjugated fluorescent silica nanoparticles give an efficient fluorescent-based immunoassay for the detection of pathogen. The synthesized silica nanoparticles were polydispersed and the size of the silica nanoparticles was in the range of 114¨C164£¿nm. The energy dispersive X-ray spectrophotometer showed the presence of silica at 1.8£¿kev and the selected area diffractometer showed amorphous nature of silica nanoparticles. The FTIR spectrum confirmed the attachment of dye and carboxyl group onto the silica nanoparticles surface. The fluorescent silica nanoparticles showed highly efficient fluorescence and the fluorescent emission of silica nanoparticles occurred at 536£¿nm. The SEM image showed the aggregation of nanoparticles and bacteria. The growth of the pathogenic E. coli was controlled using silica nanoparticles; therefore silica nanoparticles could be used in food packaging material, biomedical material, and so forth. This work provides a rapid, simple, and accurate method for the detection of pathogen using fluorescent-based immunoassay. 1. Introduction The fundamental building blocks of nanotechnology are nanoparticles [1]. The particulate dispersions or solid particles with a size in the range of 10¨C1000£¿nm are called nanoparticles [2]. Silica is encompassed of a honeycomb-like porous structure with hundreds of empty channels. Due to their unique properties such as high surface areas, large pore volumes, tuneable pore sizes with a narrow distribution, and tuneable particle diameters, currently silica nanoparticles have been intensively investigated in materials research [3]. Because of their simple preparation and possible applications in several fields, dispersed, uniform, and amorphous silica nanoparticles have produced specific interest [4]. Generally two methods are being used for the preparation of silica nanoparticles, such as microemulsion which is used to prepare the dye-doped and magnetic nanoparticles and stober method which is used to prepare pure silica and organic dye doped silica nanoparticles. The morphology of the nanoparticles can be controlled through the parameters involved in the process [5]. In stober process, due to the hydrolysis process, the ethoxy groups are replaced by TEOS; the hydrolysis reaction initiates by the attachment of hydroxyl anions on TEOS molecules [6, 7]. The condensation reaction occurs immediately after hydrolysis reaction. The Si¨CO¨CSi bridges are formed by the alcohol condensation of hydroxyl group of intermediate reaction with ethoxy group of other TEOS, or the water
%U http://www.hindawi.com/journals/jnt/2013/509628/