Quantitative differentiation of protein aggregates from other subvisible particles in viscous mixtures through holographic characterization

TL;DR

This paper presents a holographic video microscopy technique for detecting and differentiating subvisible particles in biopharmaceutical formulations, enabling precise analysis of particle types, sizes, and concentrations.

Contribution

The study introduces a novel holographic characterization method that accurately distinguishes various subvisible particles in complex mixtures, improving analysis of protein formulations.

Findings

Successfully differentiates protein aggregates from contaminants

Provides simultaneous measurement of multiple particle classes

Identifies metal particles and air bubbles clearly

Abstract

We demonstrate the use of holographic video microscopy to detect individual subvisible particles dispersed in biopharmaceutical formulations and to differentiate them based on material characteristics measured from their holograms. The result of holographic analysis is a precise and accurate measurement of the concentrations and size distributions of multiple classes of subvisible contaminants dispersed in the same product simultaneously. We demonstrate this analytical technique through measurements on model systems consisting of human IgG aggregates in the presence of common contaminants such as silicone oil emulsion droplets and fatty acids. Holographic video microscopy also clearly identifies metal particles and air bubbles. Being able to differentiate and characterize the individual components of such heterogeneous dispersions provides a basis for tracking other factors that influence the stability of protein formulations including handling and degradation of surfactant and other excipients.