A comparison of background membrane imaging versus flow technologies for subvisible particle analysis of biologics

Int J Pharm. 2020 Mar 30;578:119072. doi: 10.1016/j.ijpharm.2020.119072. Epub 2020 Jan 27.


A recently developed high-throughput background membrane imaging (BMI) technique, the HORIZON, was assessed for its ability to quantify subvisible particulate (SVP) generated during protein therapeutic development. The HORIZON platform method was optimized and compared to three well-characterized SVP counting techniques: light obscuration, micro-flow imaging (MFI), and FlowCam®. A head-to-head comparison was performed for precision, linearity, SVP concentration, and morphological output of BMI compared to the other three techniques using two unique enzymes under investigation. We found that dilution requirements for BMI are protein-specific, and membrane coverage is the critical instrument parameter to monitor for dilution suitability. The precision of BMI ranked similarly to all other techniques. Analysis of the same sample dilution, run in triplicate, across all four techniques indicated the BMI technique provides SVP concentrations that are comparable with the flow imaging techniques. Morphological information from BMI was generally less practical when compared with flow microscopy. The major drawback of BMI was that the current software indiscriminately clips large particles, potentially resulting in a misrepresentation of SVP size distribution. Despite this phenomenon, the concentration and size data generated corresponds well with current flow imaging techniques while decreasing time, cost, and sample requirements for SVP quantification.

Keywords: Background membrane imaging; Flow imaging; Light obscuration; Protein; Subvisible particles.

Publication types

  • Comparative Study

MeSH terms

  • Biological Products*
  • Image Processing, Computer-Assisted
  • Membranes, Artificial
  • Optical Imaging
  • Physical Phenomena
  • Protein Aggregates*
  • Software


  • Biological Products
  • Membranes, Artificial
  • Protein Aggregates