MS: ✗
BD: ✗

Density Matching

For more information, see:

Henrickson A, Kulkarni JA, Zaifman J, Gorbet GE, Cullis PR, Demeler B. Density Matching Multi-wavelength Analytical Ultracentrifugation to Measure Drug Loading of Lipid Nanoparticle Formulations. ACS Nano. 2021 Mar 23;15(3):5068-5076. doi: 10.1021/acsnano.0c10069. Epub 2021 Feb 22. PMID: 33617224.

Determination of Particel Size... Schmidt, Linders, Mayer, Coelfen. DOI: 10.1002/ppsc.202100079

REWRITE: Determining the amount of drug loaded into a LNP is of utmost importance for many biopharma applications. Determining the precise loading with nucleic acids is critical for achieving clinically relevant formulations, and to avoid antigenic materials in vaccines or gene therapy formulations. This can be challenging for many techniques since overall LNP size and shape may not proportionally change with the cargo load. However, the density, or partical specific volume of LNPs is a sensitive predictor of loading state, regardless of particle size, and the absorbance profiles of liposomes and nucleic acids is a unique characteristic that can be followed by AUC.

REWRITE: SVEs can be used to determine the sedimentation and diffusion coefficients, and partial concentrations of all solutes present in a sample with high resolution. In this workshop we will demonstrate how multiple SVEs performed in different D2O:H2O ratios can be used to globally fit a partial specific volume (PSV) distribution for samples that are heterogeneous in density, and to combine this information with MW-AUC information to uniquely identify the LNP loading state. Furthermore, we can combine the PSV distributions with the corresponding sedimentation and diffusion coefficient distributions to derive accurate molar mass, particle size and anisotropy distributions.

Methods

Limitations

The density matching algorithm is very sensitve to the absorbance baseline.