Stable fluorescent silicon nanoclusters, reversible interaction with solvents and applications in drug delivery

JOINT EVENT ON 15^th International PHARMACEUTICAL MICROBIOLOGY AND BIOTECHNOLOGY CONFERENCE & 10^th Annual MEDICAL MICROBIOLOGY SUMMIT & EXPO

June 21-23, 2017 London, UK

Hanieh Yazdanfar and Klaus Von Haeften

University of Leicester, UK

Posters & Accepted Abstracts: J Med Microb Diagn

Abstract :

Fluorescent silicon nanoclusters are of considerable interest, both as means of studying the fundamental properties of silicon, the most important technological material of our age, but also for their many possible applications. Luminescent clusters of silicon have applications in Drug delivery, biological labels and sensors as well as in optoelectronic devices and lasers; also its low toxicity giving it an advantage over other light emitting materials. Fluorescent silicon nanocluster solutions have been produced in our lab with a novel method using liquid jet passes through the source of atomized silicon in the vacuum (10-2) and makes the solution of silicon clusters deposit on the cold trap. In this method several ml of sample with cluster size of 1 nm will be produced in few minutes. Aging experiment proves these fluorescent particles are stable in solution after several years; their fluorescence intensity did not change during 3 years. Samples can produce in different solvents such as water, ethanol, and isopropanol. Clusters show a solvent sensitive fluorescence band at 350-420 nm and the results show peak shifts with changing the solvent, this process is reversible. The solvent exchange suggests that fluorescence originates from the solvent/cluster-surface interface. Stern-Volmer plot describes a linear relation between fluorescent yield and concentration. The silicon nanoparticles produced in water have quantum yield between 8% and 10% which is very promising for medical applications. Chemical analysis of particles using XPS and FTIR/ATR revealed that practically all the silicon was oxidized and the silicon is present in a high oxidation state. Infrared absorption bands were attributed to SiOH, SiH, SiO, SiO2 and SiO3 investigations suggest the fluorescence emerges from these oxygen rich surface states.

Biography :

Email: hy114@le.ac.uk