# Emulsion digital PCR

> **NIH NIH R44** · DPLEXBIO INC. · 2024 · $494,340

## Abstract

Project Summary
This proposed project aims to develop a new type of digital PCR platform which eliminates the
need for uniform volumes and thereby reduces the complexity, cost, and run time of digital PCR
while increasing its dynamic range. The result is a higher performance digital PCR system that
matches the simplicity, speed, and low per-assay cost of real-time PCR.
Real-time PCR maintains great popularity in clinical diagnostics, but digital PCR is superior to
real-time PCR because it provides absolute quantitation, greater accuracy at low concentrations,
and greater reproducibility. However, because it was hypothesized that uniform volumes are
required for digital PCR quantitation, current digital PCR platforms require precise microfluidic
chips and control, which result in low throughput and high per-assay costs. Here we propose to
address these limitations by developing a digital PCR system that employs variable volume
droplets created simply by shaking a sample along with PCR reagents and an oil/emulsifier mix
to create an emulsion. PCR is performed, and droplets in the emulsion are imaged and sized.
Droplets with one or more copies of a nucleic acid are identified, and nucleic acid concentration
is determined. We call this edPCR (emulsion digital PCR).
We characterized this edCPR method via computational simulations and validated it
experimentally. Simulations were used to investigate the dependence of droplet occupancy on
analyte concentration and droplet size distribution, and to estimate the accuracy of the
measured concentration in the presence of errors in measurement of droplet volume.
Simulations also provided an estimate of dynamic range for a given droplet size distribution and
statistical power. The method was validated experimentally in terms of accuracy, precision, and
dynamic range, and to rule out potential sources of biased error, such as droplet shrinking and
droplet fusion during PCR.
In the proposed work, we will develop a commercial edPCR platform that will offer the superior
performance of digital PCR while providing the high-throughput (e.g. 384 well plate operation)
and low per-assay cost of real-time PCR, which we believe will remove the barriers to the
widespread use of digital PCR in clinical assays, point-of-care settings, and large-scale testing.

## Key facts

- **NIH application ID:** 10811721
- **Project number:** 5R44AI174618-02
- **Recipient organization:** DPLEXBIO INC.
- **Principal Investigator:** Peter B Allen
- **Activity code:** R44 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $494,340
- **Award type:** 5
- **Project period:** 2023-03-17 → 2025-02-28

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10811721

## Citation

> US National Institutes of Health, RePORTER application 10811721, Emulsion digital PCR (5R44AI174618-02). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/10811721. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*