Paper Number
PO94
Session
Poster Session
Title
Investigating the structure of PEGylated nanoparticles with capillary RheoSANS
Presentation Date and Time
October 12, 2022 (Wednesday) 6:30
Track / Room
Poster Session / Riverwalk A
Authors
- Rehmann, Kelsi M. (National Institute of Standards and Technology, Center for Neutron Research)
- Murphy, Ryan P. (NIST, NCNR)
- Weigandt, Katie M. (National Institute of Standards and Technology, Center for Neutron Research)
Author and Affiliation Lines
Kelsi M. Rehmann, Ryan P. Murphy and Katie M. Weigandt
Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899
Speaker / Presenter
Rehmann, Kelsi M.
Keywords
biomaterials; colloids
Text of Abstract
Capillary RheoSANS is a recently developed high shear capillary rheometer for in situ small angle neutron scattering (SANS) characterization created at the NIST Center for Neutron Research. With this instrument, we can perform direct structural characterization of complex fluids including colloidal solutions and mRNA solid-lipid nanoparticle (SLNs) solutions at unprecedented shear rates. mRNA SLNs are used in the Pfizer/BioNTech and Moderna vaccines to prevent the spread of COVID19. Production needs have drastically increased to meet demand; in both processing and end use, the nanoparticles will likely undergo extreme deformation with shear rates on the order of 104 -106 s-1. Based on similar materials, we expect high shear rates to affect the rheology and structure of SLNs. However, to our knowledge, no reports to date systematically study the rheology of mRNA SLNs, and the structure has only recently been elucidated using small angle X-ray and neutron scattering (SAXS/SANS). The goal of my postdoctoral research is to build a library of colloidal suspensions with analogous PEGylation and concentration to typical SLN vaccine formulations and explore the structure and rheology of these analog suspensions in direct comparison to SLN solutions. By using more commonly studied colloidal suspensions, we hope to separate the effects of grafting density, PEG molecular weight, and core softness on high shear behavior.