CD BioSciences has scattering methods of electromagnetic radiation at different wavelengths to characterize the morphology, size, and hydrodynamic radius of biomolecular condensates undergoing liquid-liquid phase separation (LLPS), on length scales of tens of angstroms to microns. Here, we provide a convenient dynamic light scattering (DLS) method to achieve such measurements.

Introduction

LLPS is the primary mechanism for generating biomolecular condensates, and reproducible methods are needed to study proteins that are often severely prone to aggregation. The bulk properties of these proteins involve diffusion coefficients (hydrodynamic radii), electrophoretic mobility, and dynamic viscosity as a function of protein solution concentration at various pH values. DLS is one of the most popular light scattering techniques because it allows the reduction of particle size to 1 nm diameter. DLS is commonly used to determine the size distribution profile of small particles in suspension or polymers in solution. DLS can also be used to probe the behavior of concentrated polymer solutions, not only to detect the onset of protein aggregation in suspension, but also to detect the form and composition of these condensates.

Fig. 1. Scheme of a typical light scattering experiment. (Arzenšek D, et al., 2010)

Customized Services

Scattering methods can provide valuable information about large-scale conformational changes, oligomerization and macromolecular complexation. Based on a cutting-edge scattering technology platform, CD BioSciences offers the fastest, non-invasive and straightforward DLS method to detect the formation of large oligomers and biomolecular condensates of 0.2-3 μm in size, and allows the timely characterization of the evolution of the system under analysis.

Since DLS is based on the measurement of scattered light intensity fluctuations with time, we use this method for a wide range of different aspects of characterizing LLPS, including:

✓ Analysis of the trajectory of condensates.

✓ Analysis of the flow properties of condensates.

✓ Detection of the formation of large oligomers.

✓ Determination of the saturation concentration of phase separated proteins.

What attracts customers is that we can analyze the reversibility of LLPS in monoclonal antibody-based biotherapeutics (mAb) solutions by comparing DLS plots obtained under monodisperse conditions and after diluting the layered samples into monophasic, monodisperse, and concentrated states. In addition, in the study of elastin-like protein phase separation systems, we can use DLS to determine the bipartite profile of the phase diagram by monitoring the change in the hydrodynamic radius of the soluble complexes.

Advantages of Dynamic Light Scattering

• It is a powerful technique for studying the properties of condensates suspensions and solutions.
• Absolutely, non-intrusive and non-destructive.
• Also suitable for measuring velocity, such as measuring microorganisms floating in a solution, or analyzing flow in fluids.
• The size distribution of the condensates can be calculated and a description of the motion of the particles in the medium can be given.
• The diffusion coefficient of the condensates can be measured and the autocorrelation function used.

Our technique for DLS provides a fast way to obtain size information for the characterization of biomolecular condensates. It is very sensitive to the presence of condensates, which is a very important consideration for most pharmaceutical and biomolecular applications. If you are interested in our services, please do not hesitate to contact us for more information.