Starfruit shaped Gold (Au) nanorods synthesised at Rice University’s BioScience Research Collaborative could potentially reveal nano-applications that rely on SERS.

The Rice researchers found that nanoparticles returned SERS signals 25 times stronger than similar nanorods with smooth surfaces.  Such signal magnitude may make it possible to detect very small amounts of organic molecules, such as DNA and bio-markers, found in bodily fluids, for particular diseases.

An associate Professor of Chemistry – Eugene Zubarev – stated “There’s a great deal of interest in sensing applications,”  “SERS takes advantage of the ability of Au to enhance electromagnetic fields locally.  Fields will concentrate at specific defects, like the sharp edges of our nanostarfruits, and that could help detect the presence of organic molecules at very low concentration.”

DCN Corp - Seen from the side, the nanostarfruit produced at Rice University take on the appearance of carambola or starfruit. The particles are about 55 nm wide and 550 nm long.  Credit - Professor Eugene Zubarev, Rice University, USA

Typically SERS can detect organic molecules by themselves, but the presence of an Au surface greatly enhances the effect.  In addition, Zubarev stated “If we take the spectrum of organic molecules in solution and compare it to when they are adsorbed on an Au particle, the difference can be million of times,”  The potential Au enhancement can boost a minimal signal by a factor of 25 or above.

The researchers also sought to grow longer nanowires, which when matched with their optical advantages may reveal unique electrical properties.  Ongoing experiments with a fellow researcher – Stephan Link – an assistant Professor of Chemistry and Chemical and Biomolecular Engineering, will help ascertain the starfruit nanowires ability to transmit a plasmonic signal.  The smoothness, reproducibility and repeatability of such signals could be useful for waveguides and other optoelectronic devices.

DCN Corp - Nanostarfruits begin as Siliver (Ag) nanowires with pentagonal cross-sections. Rice chemist Professor Eugene Zubarev believes siliver ions and bromide combine to form an insoluble salt that retards particle growth along the pentagons’ flat surfaces.  Credit - Professor Eugene Zubarev, Rice University, USA

However, the primary concern of Zubarev’s laboratory remains biological.  As claimed “If we can modify the surface roughness such that biological molecules of interest will adsorb selectivity on the surface of our rugged nanorods, then we can start exploring low concentration of DNA or cancer bio-markers.  Many cancers where the diagnostics is paramount can very much depend on the lowest concentration of the bio-marker that can also be resonated.”  Full article available here.

DCN Corp believes it has also contrived a novel 9 Combination (9c) SERS dip coating protocol, which could smartly screen cancerous tumours as well as other cardiovascular conditions/diseases as an early-, mid- and late-point nano bio-marker therapeutic methodology, which could strongly compete with the claims made by the Rice University researchers.  Therefore, if you believe you or your colleagues are interested in making the above a reality – please ensure to contact the company as soon as practicably possible.