Structural and Spectroscopic Characterization of PM 597 Dye-Silica Core-Shell Nanoparticles

Tahani R Al-Biladi,Saif M H Qaid,A S Al Dwayyan,Khalid Al Zahrani,M Naziruddin Khan

doi:10.1155/2015/901032

Abstract

Nanostructured fluorescent pyrromethene (PM) doped-silica core-shell particles were successfully prepared by Stöber process. The average size of the particles was in the range of 10–20 nm measured by TEM micrograph. The atomic structure and morphology of PM 597/SiO2core/shell nanoparticles were studied by AFM and SEM, respectively. Absorption and emission spectra of the PM 597/SiO2core/shell nanoparticles under the UV irradiation were studied and not significantly influenced at the position of peaks. Finally, amplified spontaneous emission (ASE) and photobleaching of dye were examined and found no significant influence on the peaks of PM dye due to the formation of smaller sizes of PM 597/SiO2core/shell nanoparticles. The observed PM 597/SiO2core/shell nanoparticles were different in shapes with smaller size distribution and highly luminescent. Majority of nanoparticles were roughly spherical with many of them aggregated. The less photobleaching of dye core may be due to the protection of pumped energy by SiO2shell and restricts the leakage of dye.

Highlights

Preparation and analysis of fluorescent dye nanoparticles for the application of biotechnology [1, 2] and information technology applications such as biological imaging, sensor technology, microarrays, and optical computing [3,4,5,6] have been studied
Pyrromethene dye molecules were successfully entrapped as cores in silica shell with various sizes
PM 597/SiO2 core/shell NPs with thick silica shells could be obtained without affecting the integrity of the cores

Summary

Introduction

Preparation and analysis of fluorescent dye nanoparticles for the application of biotechnology [1, 2] and information technology applications such as biological imaging, sensor technology, microarrays, and optical computing [3,4,5,6] have been studied. Nanoparticles are intermediate state between molecular and bulky forms of material and can provide unique chemical, optical, and electronic properties by combining their surface modification and composition control [7]. Sol-gel derived silica is considered an excellent host material for creating fluorescent nanoparticles by the inclusion of covalently bound organic dyes. Core-shell structure of dye-silica can be substituent for fluorescent dye because silica surface can be modified to various functional groups and enhances the thermal and chemical stability of the nanoparticles with less oxidation and cytotoxicity [13]. The main aim of this work is to investigate the optical stability, ASE of PM597-core silica shell, since the PM dye has unique chemical structure and is highly luminescent

Objectives

Results

Conclusion