This Small Business Innovation Research (SBIR) Phase II project aims to demonstrate the extraordinary performance of zwitterionic technology in protein interaction analysis. Zwitterionic polycarboxybetaine (pCB) is not only highly resistant to nonspecific protein adsorption, but also has abundant functional groups for the convenient and effective immobilization of biomolecules via conventional chemistry. This dual-functional property distinguishes pCB from other existing low-fouling materials, and enables diagnostics or molecular recognition in complex media. In this project, high-quality zwitterionic materials and coatings will be scaled up with low-cost and simple production process. The expected outcome is that one can immobilize molecular recognition elements directly onto a non-fouling background for a wide range of applications.

The broader/commercial impacts of this project will be the potential to offer an effective approach in protection of surfaces from unwanted interactions in complex media for biomedical and engineering applications. Zwitterionic technology has superior advantages of low cost, stability, effectiveness and additional functionalities. For protein interaction analysis and medical diagnostics, this technology will improve the sensitivity and specificity of a biosensor, and enable the detection of analytes in undiluted human blood plasma and serum.

Project Report

Zwitter Technology is developing materials and methods for making surface coatings from carboxybetaine polymers. Remarkable for their ultra-low fouling (ULF) properties, our coatings have a broad array of applications including biosensing, clinical diagnostics, medical devices, drug delivery systems, and subsurface marine coatings. The primary application that was pursued for this Phase II SBIR was the optimization of the coatings for surface plasmon resonance (SPR) biosensing chips. SPR is a highly sensitive biosensor that enables detailed evaluation of molecular interactions, which has applications in fields such as clinical diagnostics; pharmaceutical discovery and development; and food safety. Producing ULF coatings for SPR chips acted not only as the first commercial product of interest, but also allowed Zwitter Technology to evaluate our coatings in a highly detailed manner; such evaluations enabled fine-tuned development of the technology, which has set the stage for additional commercial applications that benefit from ULF coatings. This NSF Phase II SBIR award has supported the technical development necessary for the commercialization of our technology. Commercial applications first require a reliable and scalable production process, so this was the first task that was undertaken with the funding. Secondly, in order to achieve the important milestone of demonstrating a successful application of the coatings, Zwitter Technology focused our product development on SPR biosensing chips. At the end of the NSF Phase II award period, Zwitter Technology is able to produce coated SPR chips at a commercially-relevant cost and scale. In addition to producing the chips, we developed the experimental techniques required to use them in a variety of settings. These technical advancements have also readied the technology for applications beyond SPR biosensing. Our work on SPR chips has resulted in a collaboration with a large company in the SPR industry. We are also engaged with several companies discussing collaborations for other applications of the technology, demonstrating the great demand for the coatings that were developed under this award.

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Zwitter Technology, LLC
United States
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