From Nanograms to Micrograms
The difference between detecting cancer and missing it often comes down to how much DNA you have to work with. Plasma-Sieve changes that equation.
Why Input Quantity Drives Everything
Liquid biopsy sensitivity is fundamentally constrained by the amount of cfDNA available for analysis. A standard 10 mL blood draw yields roughly 6,000 human genome equivalents (hGE) of cfDNA. When tumor-derived ctDNA represents only 0.01% or less of that total, you are searching for fewer than one mutant molecule in the sample.
At that scale, detection becomes a matter of chance. Most assays will miss the signal entirely, not because the technology failed, but because the input was insufficient. Plasma-Sieve resolves this at the source by delivering 300,000 to 1,200,000 hGE per collection.
Ultra-Deep cfDNA Libraries
Microgram-scale cfDNA inputs allow the construction of ultra-deep next-generation sequencing (NGS) libraries. Greater input depth means more unique molecules sequenced, lower variant allele frequency (VAF) thresholds, and higher confidence variant calls across multi-cancer early detection panels.
Digital PCR for MRD
For tumor-informed minimal residual disease (MRD) assays using digital PCR, larger cfDNA inputs translate directly to lower limits of detection. With Plasma-Sieve, the analytical LOD for cfDNA tumor markers improves by 100- to 1,000-fold, enabling detection of residual disease at concentrations that would be invisible to a standard blood draw.
The Poisson Principle
Detection probability for rare variants follows Poisson statistics: the probability of observing at least one mutant molecule is P = 1 - e(-N·f), where N is the number of genome equivalents sampled and f is the variant allele frequency.
At VAF = 0.001% and 6,000 hGE (standard draw), detection probability is essentially zero. At 300,000 hGE with Plasma-Sieve 50x enrichment, that same signal becomes reliably detectable. Our interactive model on the Platform page lets you explore this relationship directly.
Key Outcome
100x to 1,000x improvement in analytical limit of detection for digital PCR MRD assays, driven entirely by increased cfDNA input.