L/D-Analysis
For the precise and rapid enumeation of living bacteria in probiotic products
L/D analysis for the quality assurance of probiotics
Probiotic products contain living microorganisms that support intestinal health. However, the effectiveness of these products is directly connected to the number of living bacteria. With the live/dead analysis (L/D analysis), we offer a reliable, fast and precise method to monitor and guarantee the viability of the bacteria inside the probiotic sample.

Figure: Differentiation of living and dead cells using flow cytometry, based on staining with a green and a red fluorescent dye, which differentiate intact from damaged cell membranes.
The advantages
High precision: Reliable differentiation between living and dead bacterial cells.
Rapid results: Thanks to high-throughput and automated process using flow cytometry
High sensitivity: Through the use of specific fluorescent dyes.
Wide range of applications: Ideal for various probiotic products and samples.
Why is the L/D analysis important?
- Quality assurance: L/D analysis makes it possible to differentiate between dead and living bacteria, which are active in probiotic products and offer health benefits.
- Stability monitoring: L/D analysis enables monitoring of the vitality of the bacteria during storage to ensure that the products maintain their shelf life and effectiveness.
- Consumer confidence: Probiotic products must have minimum levels of living bacteria. L/D analysis helps manufacturers meet the highest standards and gain the trust of their consumers.
Specific cell enumeration with Flow-FISH
For a specific quantification of the different microorganisms in probiotic products, we recommend our Flow-FISH / VIT® technology, which allows for the live quantification of specific bacterial species. This ensures that the desired microorganisms are present in the correct concentration in your products.
You can also learn more about this topic in the webinar "Specific Enumeration of Probiotics with Flow-FISH".