The concentration of this non-dimerized dye inside of the particles is several thousands times higher than the maximum concentration of the dye that can be reached without dimerization just in an aqueous solution.

Comparing fluorescence spectra and quantum yield of the encapsulated and free dye, indicates that the dye is physically entrapped inside the silica nanotubes. Therefore, the brightness of the dye is not decreased as it might be in the case of chemical binding to the silica wall. The topology of the synthesized particles is such that the silica tubes are self-sealed, and consequently, there is virtually no leakage of the dye out to these particles.

Using a mix of several dyes in one synthesis, gives the mixture of dyes, virtually a new color, inside of each particle. Simple estimation shows that the amount of such combinations of dyes is practically unlimited. Fluorescence of these particles is very stable. See Figure 5.

This novel discovery for making ultrabright silica fluorescent particles is being developed further in collaboration with Dr. Naik, a postdoctoral fellow in Professor Sokolov’s group. They have exchanged a fairly expensive organic silica precursor for a rather cheap inorganic silica source. Also using the advantages of one dimensional confinement of the dye molecules, Dr. Naik and Professor Sokolov, together with a Ph.D. student Volkov, developed a new type of thermal sensor. Using this approach, the researchers hope to develop an entirely new platform, a “laboratory on a particle”.

For more information about Professor Igor Sokolov and his research, you may call him at 315-268-2375 or send email to isokolov@clarkson.edu.

 Professor Devon Shipp

CAMP Professor Devon Shipp and Bausch and Lomb Enter into a Research Contract to Develop New Contact Lens Materials  

CAMP Professor Devon Shipp and world-leading eye-care company Bausch and Lomb, based in Rochester, New York, have entered into a research agreement for the development of new contact lens materials. The development of new polymers that will form the basis of future contact lens materials is of great importance to the eye care industry. However, significant work is required to develop new polymer materials that have high oxygen permeability, in addition to high water wettability and transport. The eye needs oxygen to breathe, since no blood is carried into the eye. Also to prevent lens adherence to the cornea, the lens must be hydrophilic. In order to achieve such properties, and many other basic materials properties such as strength and tear resistance, the contact lens industry has looked at combining silicones, which impart high oxygen permeability, with hydrophilic polymers to allow the gel to swell in water and give wettability. However, these two types of materials typically do not mix well together. Thus some smart molecular engineering is required to ensure contact lenses that not only provide improved vision, but are also comfortable.

This joint project stems from Professor Shipp’s six month stay at the Research and Development laboratories of Bausch and Lomb (B&L) during his recent sabbatical leave. While there, he introduced B&L to novel forms of polymerizations that allow for the production of well-functionalized polymer materials that can be used in contact lens formulations. It is anticipated that this work will develop a greater understanding of structure-property relationships which will then provide the means by which new and improved lenses can be made. See photo.

For more information about Professor Devon Shipp and his research, you may call him at 315-268-2393 or send email to shippda@clarkson.edu.