April 20, 2020 – Rapid Viral Titer with Spectradyne’s nCS1^TM

Measuring the viral titer, the concentration of viruses in a sample, is an important procedure in virology. The modern fast pace of research and the current race to develop a vaccine for the COVID-19 pandemic highlight the necessity for a rapid and easy methodology for virus quantification.

Conventional approaches to viral titer are time-consuming, labor intensive and often suffer from poor reproducibility. Plaque titer and fluorescence focus assay (FFA) techniques require serial dilutions of the virus stock and the waiting period for cell infection and incubation can last for days. Other methods such as quantitative polymer chain reaction (qPCR) and enzyme-linked immunosorbent assay (ELISA) can be completed in hours but qPCR is sensitive to contamination and ELISA is highly selective and necessitates the prior knowledge of specific antibody-antigen interaction. Transmission electron microscopy (TEM) quantification is expensive and requires tedious sample preparation and a highly skilled operator.

Spectradyne’s microfluidic pulse sensing (MRPS) technology delivers a complete and accurate analysis within minutes and consumes less than 3 microliters of sample. The Spectradyne’s nCS1^TM system utilizes disposable microfluidic cartridges, eliminating cross-contamination between samples and allowing for rapid testing of high number of samples.

With non-optical electrical sensing technology, the nCS1^TM can detect and quantify virus particles directly in complex biological samples, saving substantial amount of sample preparation time. The system is practical, highly automated and easy to use.

Comparison table of the time and labor cost of virus titer techniques:

Technique	Method	Reproducibility	Time	Labor	Cost
MRPS (nCS1)	Viral particle	Excellent	Minutes	Low	Inexpensive
Plaque titer	Infectivity assay	Poor	Days	High	Inexpensive
FFA	Infectivity assay	Poor	Days	High	Expensive
qPCR	Viral nucleic acid	Excellent	Hours	Moderate	Expensive
ELISA	Viral protein	Good	Hours	Moderate	Inexpensive
TEM	Viral particle	Excellent	Weeks	High	Expensive

Human adenovirus sample characterized with Spectradyne’s nCS1^TM.

Human immunodeficiency virus (HIV, inactivated) characterized with Spectradyne’s nCS1^TM.

Murine leukemia virus sample characterized with Spectradyne’s nCS1^TM.

The virus measurement examples above showcase the nCS1’s ability to detect a broad variety of viruses, from human adenovirus and HIV virus to murine leukemia virus. The size and concentration of the virus sample was measured accurately and rapidly within minutes.

Spectradyne’s technology is affordable, easy to use, and easy to adopt. Want to learn more about how it saves virologists time? Visit our virus applications page here.

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