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Using Light Obscuration? Can you afford to miss protein aggregates?

Reduce Recall Risk with MFI

Particulate matter contamination was the second highest cause of recall by the FDA in 2016. Current contamination detection methods, like Light Obscuration (LO), are limited in their ability to detect all particulate matter. Why? Protein aggregates are often highly translucent and therefore missed by compendial methods. Work done by the National Institute of Standards and Technology has shown that Light Obscuration is less sensitive to particles whose refractive index closely matches the surrounding matrix. This leads to both undercounting and under-sizing of protein aggregates.


Figure 1 (Right). MFI can detect more sub-visible particles compared to pharmacopeial methods such as Light Obscuration and Manual Microscopy. Because MFI's novel imaging technology is more sensitive, it can see the translucent protein particles that these older methods can miss.

Protein aggregation analysis using Micro-Flow Imaging (MFI) versus light obscuration graph


Micro-Flow Imaging™ combines the direct imaging capabilities of digital microscopy with the precise control of microfluidics. Therefore, you get a complete image of what passes through the flow cell. Even translucent protein aggregates that would be missed by LO are caught by MFI. From those images morphology is derived which can then be used to differentiate particle populations within the sample. With a more sensitive detection method and the ability to separate protein from non-protein MFI gives you the most complete profile of particles in your sample.


Figure 2 (Right). MFI’s high sensitivity allows it to detect translucent particles, like protein aggregates, that are invisible to traditional methods like Light Obscuration. Its image-based approach allows MFI to distinguish between different particle populations within a sample, including protein aggregates, silicon oil and other contaminants.

Micro-Flow Imaging Diagram

Watch this video to learn how MFI gives you the most complete profile of particles in your sample

Seeing Beyond Light Obscuration with Micro-Flow Imaging

What others are saying about MFI


"MFI technology has allowed us to better understand what conditions promote stability of our therapeutic molecules, which ensures that only world-class medicines are delivered to patients."

  • Stephanie Davies, Ph.D., Formulation Sciences, Medimmune

"We’re able to do extended analysis with images provided by MFI and then bridge this data with other techniques to identify and rapidly classify particles in solution. This helps our clients understand their products better and ensure they are providing the highest quality product to their patients."

  • Amber Fradkin, Ph.D., Associate Director, Particle Characterization Core Facility, KBI Biopharma