A precise label-free method to measure the shape and composition of model condensates has been published by Brugués and Hyman labs from Max Planck Institute of Molecular Cell Biology and Genetics.

Many protein-rich biomolecular condensates have been detected in eukaryotic cells whether in the cyto- or nucleoplasm and have shown integral roles in many cellular processes. The newly published approach offers a method that can be used to measure the refractive index of micron-size droplets in situ as well as the protein concentration in condensates with high precision.

The method is basically dependent on measuring the phase across droplets using holographic microscopy namely Q-Phase. Q-Phase based on coherence controlled holographic microscopy offers very high phase measuring sensitivity thus generating high-quality quantitative phase imaging for measurements of individual um-sized condensates composition. They found that measuring the individual droplet compositions using Q-Phase introduces a practical method with better precision compared to any other comparable technique.

Read the article “Quantitative phase microscopy enables precise and efficient determination of biomolecular condensate composition“.