The Power of a Laboratory in the Palm of Your Hand.
Meet CaDI
The capillary-driven immunoassay (CaDI) delivers ELISA-like sensitivity at a fraction of the cost and complexity.
The CaDI platform is enabled by chemiluminescence. Chemiluminescence has long been recognized as the most sensitive protein detection modality, but has never been implemented at the point-of-care due to the requirement of sophisticated assay timing and optimization.
We’ve developed a chemiluminescent reader sensitive enough to detect as few as five photons. When paired with the CaDI microfluidic device, which enables precisely timed reagent delivery, it supports the sequential assay steps required for ultrasensitive chemiluminescent detection—something traditional rapid antigen tests cannot achieve.
In lateral flow assays (LFAs), reagents flow together along a linear path, limiting the ability to control timing or sequence without additional user steps. This makes LFAs fundamentally incompatible with high-sensitivity chemiluminescent readouts. Thus, chemiluminescent tests have been limited to central labs that require highly trained personnel and expensive equipment.
CaDI’s sensitivity advantage over traditional LFAs using chemiluminescent detection is demonstrated in the figure.
CaDI consistently achieves a much higher signal-to-noise ratio (SNR) across all concentrations, as seen across the chemiluminescent images (top panel), intensity line plots (middle panel), and heat maps (bottom panel).
The CaDI Cartridge
The capillary-driven immunoassay (CaDI) device is constructed of multiple layers of polyester and adhesive. These materials are used to create hydrophilic channels with integrated reagent pads. Additionally, there's a nitrocellulose strip with printed capture antibodies, where binding occurs and the signal is generated for the final result readout.
Reagents embedded in the device are released sequentially and delivered to the test lines with controlled timing and order. This timing can be adjusted through simple changes to the channel geometry. The device is made from common, inexpensive materials and is designed for low-cost manufacturing.
The Reader
All CaDI test cartridges are integrated with our chemiluminescent reader system for quantitative or qualitative result analysis. After sample addition to a CaDI cartridge, insert the cartridge into the reader for rapid 10-minute results.
*Video is for demonstration purposes only. Actual time to result may vary.
How It Works
All steps of a traditional ELISA are programmed onboard the cassette, including:
1. Sample delivery to the capture antibodies
2. Label antibody delivery
3. Washing of unbound material
4. Delivery of enzyme-substrate for signal generation and amplification
The role of the microfluidic network is to achieve tied sequential delivery of test reagents to the test region.
CaDI vs. ELISA
Traditional ELISA workflows, even when using precoated and preblocked plates, typically take three or more hours to complete and require multiple manual steps. In contrast, the CaDI platform delivers equivalent analytical performance in just 10 minutes, with no pipetting, washing, or timers needed from the user.
Watch the video below for a side-by-side comparison of a ~3.5-hour ELISA and a 10-minute CaDI test.
Fully automated immunoassay in a cassette. All steps of chemiluminescent ELISA (binding, washing, labeling, amplification) are performed in the microfluidic device and fully powered by capillary action with no manual intervention.
Sensitivity and specificity. Improvements of 100-1000x over traditional lateral flow tests have been demonstrated in the laboratory.
Adaptable. This system can be adapted towards any analyte with appropriate antibody pairs available by changing the reagents immobilized on the pads in the device. Reach out to learn more about our partnering opportunities. Let us bring your assay to the light!
Manufacturable. The fluidic architecture of our test cassettes are constructed with common, low-cost materials. Assembly of these devices can be readily scaled up rapidly using reel-to-reel manufacturing.
Custom Assay Solutions
Discover how our cutting-edge technology can be customized for your application. Visit the custom assay solutions page to see how CaDI supports industry-specific needs.
Peer-Reviewed Publications
For additional validation and technical detail, explore our peer-reviewed publications highlighting the development and performance of the CaDI platform.