Flowdls - inline sizing of nanoparticles by dynamic light scattering

flowDLS is an inline measurement system developed by Fraunhofer IMM that uses Dynamic Light Scattering (DLS) to determine nanoparticle sizes directly in a flowing liquid stream, enabling real-time characterization during synthesis or processing.

Nanoparticle size and size distribution are critical for product performance in areas such as nanomedicine, pharmaceuticals, and advanced materials. Conventional offline analysis is time-consuming and limits process insight. flowDLS enables immediate feedback, supporting faster development, improved quality control, and continuous manufacturing.

Particles scatter laser light while flowing through the measurement cell. Fluctuations in the scattered light caused by Brownian motion are analyzed using DLS principles and the Stokes–Einstein equation. Advanced signal and image processing suppress flow-induced disturbances, allowing accurate size measurement even at high flow rates.

flowDLS has been validated in microreactor setups, where it successfully monitored the synthesis of niosomes and silica nanoparticles. It was able to detect rapid size changes in response to process adjustments, and it has been applied to inline measurements within microfluidic chips for lipid nanoparticles, demonstrating process transparency and responsiveness.

flowDLS is designed for integration into industrial process environments, enabling online monitoring and feedback-controlled nanoparticle production. Future work focuses on broader industrial adoption and tighter coupling with process control systems.