Virus Analytics

Rapid Virus Quantification

Products from ViroCyt, now part of Sartorius Stedim Biotech, are leading the field of rapid virus quantification. Our goal is to provide the tools that deliver meaningful improvements to mission critical processes, where viruses play a significant role.


  • Vaccine production
  • Protein expression
  • Viral therapeutics
  • Antiviral development

Our virus quantification products offer a new approach to enable direct, biologically-specific quantification of viruses in minutes, rather than the days or weeks required by more traditional methods. Virus samples are labeled with specifically-developed reagents in a no wash assay. The purpose-build platform enables quantification of total virus particles in three minutes per the sample, giving users real-time insights into viral titers.

Meet The Virus Counter Platform: The Powerful Tool for Rapid Virus Quantification

The Virus Counter® Platform is in use by leading companies, regulatory agencies, and research agencies around the world. Why? A growing body of evidence demonstrates that noninfective particles are of biological importance and can impact both in vitro and in vivo studies. Infectivity and total particle concentration are essential for an in-depth sample characterization.

The Virus Counter Platform Delivers More of What Matters When Quantifying Viruses

  • Speed - Real-time quantification for process monitoring and production optimization
  • Biologically-relevant readout – Total viral particle quantification
  • Versatility - High-specificity and universal quantification reagents
  • Ease of use – software-assisted system operation (including 21CFR Part 11 capabilities)
  • Reliability – Rugged design for industrial settings, easy system maintenance

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Versatility - More than you can count

Our Combo Dye™ reagent and ViroTag® reagents offer the optimal solution for all virus quantification needs.

The number of viruses and virus like particles (VLPs)  quantifiable by the Virus Counter® platform are almost limitless.

With the Virus Counter® Platform, use our rapid, no wash procedure and take virus quantification to new levels of accuracy, speed and simplicity

ViroTag® Reagent

The ViroTag® detection system provides mission-critical data in real-time. This novel technology enables direct, biologically specific quantification of viruses. by utilizing a fluorescently-labeled, high-affinity antibody which binds to a unique epitope expressed by your virus of interest.

Use the ViroTag® reagents to label your virus samples and analyze on the Virus Counter® instrument.

Enables real-time tracking of virus titer in your process:

  • Optimize growth conditions
  • Maximize yields
  • Identify problems sooner

ViroTag® Reagent Kits

AAV2-3for Adeno-Associated Virus Serotypes 2, 3
INVXfor Influenza Virus
BCVBfor Baculovirus

for pseudo typed viruses such as Lentivirus or BacMam

INVAfor Influenza A seasonal flu virus
INVBfor Influenza B seasonal flu virus

Combo Dye™ Reagent

The Combo Dye™ detection system is very simple and universal approach to quantify enveloped viruses with single- or double-stranded DNA or RNA genome. This universal reagent is based on a dual strain approach which identifies intact virus particles by a simultaneous detection of protein and nucleic acid signal. The use of fluorogenic dyes eliminates the need to wash.

Simple, No-Wash Assay

Both Combo Dye™ and ViroTag® labeling systems use a rapid, no wash-assay workflow.

With the Virus Counter® 3100 platform, use this rapid, no wash labeling procedure and take virus quantification to new levels of accuracy, speed and simplicity.

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