Nano-Encapsulation Using GRAS Materials

Web Published:

Nanoparticle Compositions and Methods using Gras Materials for encapsulation and delivery of active pharmaceutical ingredients

Princeton Docket # 15-3169


Researchers in the Department of Chemical and Biological Engineering at Princeton University have developed a new nano-encapsulation process using generally recognized as safe (GRAS) material. Through this novel synthesis process, components of the core and coating are kinetically assembled in a continuous, low-energy, self-contained micromixing system. The process uses amphiphilic, water-insoluble protein-based polymers such as the prolamine zein that kinetically assemble around a hydrophobic core material such as alpha-Tocopharol acetate using Flash Nanoprecipitation (FNP).  FNP is currently a Princeton patented technology to prepare nanoparticle composites with amphiphilic copolymers.  FNP is effective in encapsulating active ingredients at high particle loadings which has not been achieved by other processes.



Technology Background


These composite nanoparticles can be used as proteinaceous size standards and as encapsulation and delivery vehicles for pharmaceuticals, nutraceuticals, cosmetics, biomedical therapeutics, and diagnostic applications. This approach represents a major advance over previous methods because it uses a less expensive polymer that is bio-sourced, biodegradable, and classified as a GRAS substance by the FDA. The entire process uses GRAS substances only and the ethanol solvent is recycled by evaporation/condensation which makes the process self-contained. The new fabrication methodologies are both scalable to industrial production levels and allow for reliable production of nanometer-sized particles, two critical aspects of the production process that have thus far not been achieved using the same fabrication process. This fine control over size and particle distribution also allows these nanoparticles to be used for protein size standard applications. Finally, in proof of concept experiments with zein, these nanoparticles have the ability to encapsulate both hydrophobic and hydrophilic molecules such as DNA, RNA and proteins for effective drug delivery.





•       Protein size standards


•       Encapsulation and excipient delivery vehicle of active pharmaceutical, nutraceutical, cosmetic, and biomedical therapeutic ingredients including both hydrophobic and hydrophilic drugs





•       Produces protein nanoparticles with a defined size and narrow size distribution


•       Proof of concept performed with zein, which is bio-sourced, inexpensive, and classified as GRAS


•       FNP is scalable and amenable to GMP process needs



Key Words

Generally recognized as safe (GRAS), zein nanoparticles, flash nanoprecipitation, excipient, drug delivery, RNA, DNA, proteins




Nikolas T. Weissmueller is a postdoctoral research associate in the Department of Chemical and Biological Engineering at Princeton University. He obtained his bachelor’s degree in Biomedical Science from Harvard University, his M.Sc. in Biomedical Engineering at the University of Oxford, and his Ph.D. in Pediatrics with the Oxford Vaccine Group where he developed a novel vaccine delivery platform. His current research focuses on targeted cancer therapeutics and the formulation of nanoparticle vaccines.


Robert K. Prud’homme is a Professor of Chemical and Biological Engineering and the Director of the Program in Engineering Biology at Princeton University. His research focuses on how weak forces at the molecular level determine macroscopic properties at larger length scales. Equal time is spent understanding the details of molecular-level interactions using NMR, neutron scattering, x-ray scattering, or electron microscopy and making measurements of bulk properties such as rheology, diffusion of proteins in gels, drop sizes of sprays, or pressure drop measurements in porous media. A major focus of his lab’s research is on using self-assembly to construct nanoparticles for drug delivery and imaging. His work is highly interdisciplinary; many of the projects involve joint advisors and collaborations with researchers at NIH, Argonne National Labs, CNRS in France, or major corporate research.



Intellectual Property Status

Proof of concept studies have been completed and are available under confidentiality.


Patent protection is pending. The synthesis of nanocarriers uses Flash Nano Precipitation (FNP), has been successfully patented (US 8137699) and continuation applications are pending.


Princeton is seeking to identify appropriate partners for the further development and commercialization of this technology.



Laurie Tzodikov

Princeton University Office of Technology Licensing • (609) 258-7256•


Anna Trugman 

Princeton University Office of Technology Licensing •




Patent Information:
For Information, Contact:
Tony Williams
Princeton University
Nikolas Weissmueller
Robert Prud'homme