Pathogen Detection with iPLEX® Assays

Accurate, Sensitive, Specific.

The MassARRAY System for iPLEX assays has been routinely used for genotyping, however, more recently it has gained significant recognition for rapid, accurate pathogen detection. The iPLEX assay combines the benefits of a simple reproducible primer extension reaction chemistry with MALDI- TOF mass spectrometry to quickly and cost effectively characterize genotypes with the highest level of accuracy and sensitivity. The application complements the molecular typing functionality of the iSEQ™ software by enabling accurate, sensitive detection of the genetic target of interest.

Key features include:

• Routine multiplexing at 36- plex level (PCR and iPLEX)
• Broad throughput ranges from few hundred to 100,000 genotypes /day
• Greater than 99.7% accuracy
• Highly reproducible
• Rapid and efficient assay design software
• Convenient automated data analysis and data reporting

The sensitivity of the MassARRAY technology for molecular detection is superior to that of real time fluorescence based or in situ hybridization assays. A study on HPV conducted by the University of Michigan illustrates the high sensitivity of the MassARRAY for the detection and identification of HPV – DNA associated with several tumor types in serum and/or peripheral-blood samples, enabling the monitoring of cancer occurrence and treatment of malignancies and dysplasias associated with HPV DNA, [Source: PNAS, 2005, Vol 102, pgs. 7683 – 7688].

Direct sequence analysis of the pathogen, particularly at a population level, is generally time-consuming, technically challenging, and costly. The study on SARS- CoV conducted by the Genome Institute of Singapore illustrates that detection by the MassARRAY Mass Spectrometry offers a cost-effective, sensitive method for characterizing sequence variations of SARS-CoV in large-scale population studies. According to this analysis, the MassARRAY can detect as little as 75 copies of viral RNA with 95% probability. Furthermore, the MassARRAY provides detection of heterogeneous SARS-CoV viral sequences in single samples, demonstrating high accuracy in characterizing sequence variations, [Source: PLoS Medicine, Vol 2, pgs 162 -168].

The MassARRAY demonstrates a superior advantage for accurate, cost-effective large scale microbial and viral detection. The method is cost-effective since only a small amount of starting material is required while the multiplexing capability greatly reduces the cost per reaction down to as little as $.03 per genotype.