TECHNICAL NOTE
Sizing accuracy and intra-assay precision of DLS
measurements with Prometheus Panta
Introduction
Prometheus Panta uses nano differential scanning fluorimetry (nanoDSF), dynamic
light scattering (DLS), and backreflection for high-resolution, multi-parameter stability
characterization. The simultaneous collection of data on thermal unfolding, particle
sizing, and aggregation throughout the entire thermal ramp allows for the identification
of the temperature at which the protein unfolds, forms amorphous aggregates, or even
begins to change size or polydispersity.
Scientists in the field of drug discovery, particularly biologics, use DLS to make critical
decisions about drug candidate stability. This creates a need for instruments that exhibit
strong sizing accuracy and precision. These properties can be evaluated using standards
and references from the National Institute of Standards and Technology (NIST). Here, the
NIST monoclonal antibody (NISTmAb) reference material (RM) RM8671, Lysozyme, and
a set of monodisperse particle size standards were used to test the sizing accuracy and
intra-assay precision of Prometheus Panta's DLS optical module.
Results
Sizing accuracy
The sizing accuracy was assessed by measuring the hydrodynamic radii (r
H
) of different
particle size standards from Thermo Fisher Scientific that ranged in diameter from
approximately 20 nm to 1 µm. Prior to DLS measurement, each size standard was
sonicated for 60 seconds and, in case of the 20, 60, and 100 nm particles, diluted 1:100 in
Philipp Schramm, Silvia Würtenberger, Christian Kleusch
NanoTemper Technologies GmbH, Munich, Germany