SBIR Phase I: An instrument for Analysis and Purification of Nanoparticle Drug Delivery Using an Novel Optical Resonator

The broader/commercial impact of this Small Business Innovation Research Phase I project will be the development of a key enabling technology: a high-power optical cavity with an integrated microfluidic cell. This technology will enable a host of applications in which a material in a microfluidic channel is exposed to a high-intensity laser beam or a standing wave optical field for the purpose of either characterizing or improving the material. One example is the characterization and purification of the nanoparticles used in nanomedicine. Nanomedicine can also be described as targeted drug delivery using nanoparticles, a recently developed approach to attacking resistant diseases. Over half of existing nanomedicines are used for treating cancer. This project will make nanomedicines more effective, more affordable, and safer for millions of Americans fighting cancer and many other devastating diseases. This project will also benefit industries in which nanoparticles are utilized, including semiconductor manufacturing, airborne and water-borne threat detection, and rapid disease diagnosis. This project will address the challenges of making a resonant optical cavity that also contains a microfluidic device. The presence of any component inside an optical cavity is a potential challenge to maintaining the cavity’s resonance features including finesse. Even an optical quality element has finite reflection due to index of refraction differences that can create multiple resonance if the surface is aligned with the cavity’s optical axis or losses if the surface is not aligned. More challenging is the presence of a microfluidic channel containing a liquid. Common microfluidic devices are rarely optical quality and those that are near-optical quality don’t have all the optical characteristics required to exist inside an optical cavity without unduly perturbing the cavity resonance. The ability to create circulating intensities that are high enough to steer nanoparticles presents additional challenges. Among these is the heating of intra-cavity materials and cavity mirrors that shift cavity resonances dynamically and make cavity locking a real challenge. This project will address these challenges by testing and implementing new materials and new geometries to achieve a stable frequency-locked optical cavity with circulating powers high enough to change the trajectories of biological particles of the type used in nanomedicine. It is highly desirable to shorten the cavity length as much as possible, but this conflicts with certain design aspects of a microfluidic device. Resulting modifications will test the limits of manufacturability, another critical constraint on design. Manufacturability will be explored with external custom manufacturers of optical components and microfluidic devices. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.