Nanomaterials for Biological Research
Our group focuses on the development of bio-friendly nanomaterials that can be utilized in cell biology research and biosensing. Our expertise is in the area of nanosprings and nanowires. The nanosprings are silica, while the nanowires are silica, gallium nitride and zinc oxide.
We have focused on these materials because they are either bio-friendly either because they occur naturally in the body, or are safe to ingest, or because they are so inert they cannot be broken down by the body's immune system, or at this time there is no evidence of breakdown. With the help of our colleagues in the BANTech program we engineer the surface of the nanosprings and nanowires to promote chemical interactions that are useful for specific applications, such as gene knockdown or drug/chemical delivery. We are working to develop biosensors and DNA microarrays utilizing silica nanosprings as the sensor platform.
In addition to nanomaterials synthesis, we use x-ray photoelectron spectroscopy (XPS) to determine the interaction of chemicals with the surface of the nanomaterials. XPS allows us to probe the electronic structure of the surface of the nanomaterials, the adsorbed chemicals, and the interaction of the adsorbates with the nanomaterials. These studies allow us to determine if a chemical physisorbs, covalently bonds, or ionically bonds to the nanomaterial. If the biological application of the nanowire or nanospring requires that chemicals be delivered to the cell and subsequently released into the cell, the bond of the chemical to the nanomaterial must be strong enough to withstand being washed away when in solution, but weak enough to be released upon internalization.
What is a nanowire?
A nanowire is a wire that is typically hundreds of nanometers in length, if not more, but less than 100 nm in diameter. The image below is a scanning electron microscope image of a mat of silica nanowires.
What is a nanospring?
A nanospring is a nanowire that grows in the form of a coil. The figure below on the left is a scanning electron microscope image of a mat of silica nanosprings and the image on the right is a transmission electron microscope image of an individual nanospring. Some nanosprings consist of one nanowire, while others consist of multiple nanowires intertwined to form a nanospring.
What is a nanospring sensor?
A nanospring sensor is a sensor that is constructed with a mat of nanosprings, where the nanosprings serve as the material that promotes sensing. The figure below on the left is a scanning electron microscope image of a channel of an aqueous sensor, where nanosprings are only at the bottom of the channel and on the right a close up of the channel that shows the nanospring mat in more detail.
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