Virus Plaque Assay Service

Creative BioMart Vir-Sci is a recognized expert in virus titering service. We have a mature virus titering service platform that can provide rapid and satisfactory virus titering service according to customer needs. We offer virus plaque assay service for customers, ensuring high quality and high efficiency. In addition, we also provide services for virus TCID₅₀ assay.

Introduction

Virus quantification refers to determining the virus concentration by calculating the number of viruses in a specific volume. It is used in academic laboratory research and development and in industrial production situations where the number of viruses is an important parameter. For example, the quantification of virus is necessary in the production process of viral vaccines, recombinant proteins using viral vectors, and viral antigens to continuously improve and monitor this process, thereby optimizing production yields and adjusting to the changing needs and applications of culture. Examples of specific needs to quantify known viruses include clone screening, multiple infection optimization, and adjustment methods to adapt to the cell culture.

Fig 1. High throughput plaque overlays. (Baer, et al. 2014)

Plaque Assay Principle

The plaque-based assay is an industry standard assay used to determine the virus concentration based on the infection dose. The number of plaque forming units (pfu) in the virus sample can be determined by measuring the virus plaque. The assay is a microbiological method based on petri dishes or multi-well plates. Specifically, in order to perform a plaque assay, it is necessary to prepare a diluted virus stock solution (the lysed virus has been serially diluted to a countable range, usually 5-100 virions) and a susceptible monolayer cell for inoculation. After incubation, the cell monolayer is covered with agar medium, which can form a gel to attach the virus to the cells. When incubated with the culture plate, the initially infected cells are lysed by the virus and virus offspring are released. Due to space constraints, the new virus can only infect adjacent cells. By repeating the infection-lysis process, the infected cell area will form a plaque (an infected area surrounded by uninfected cells), which can be observed with an optical microscope or the naked eye (by adding crystal violet solution to stain, the living cells are stained purple, the location of dead cells is colorless). Plaque formation may take 3 to 14 days, depending on the virus analyzed. Finally, by counting the plaques and combining the statistical results with the control group, the number of plaque forming units per unit volume per sample can be calculated (pfu / mL).

Our Advantages

• Ensure high efficiency and quality for virus titering services
• Competitive price in the market of virus titering services
• Suitable for the titration detection of multiple virus
• Ensure 24/7 online service and short feedback cycle

Workflow of Microbiology Services at Creative BioMart Vir-Sci

Creative BioMart Vir-Sci has an expert team that own extensive experience in the field of virus titering, involving various viruses and technical methods. We guarantee that each specific experimental step in the process of virus plaque assay service is strictly controlled to ensure the provision of high-quality virus titering service. If you are seeking for related services, Creative BioMart Vir-Sci may be your good choice, please feel free to contact us, our expert team will design suitable technical solutions according to your needs, and provide you with professional and thoughtful services.

References

1.  Baer, A.; Kehn-Hall, K. Viral concentration determination through plaque assays: using traditional and novel overlay systems. Journal of Visualized Experiments. 2014, 93: 52065.
2.  Yakimovich, A.; et al. Plaque2.0—a high-throughput analysis framework to score virus-cell transmission and clonal cell expansion. PLOS One. 2015,10 (9): e0138760.