This technology enables automatic control and programming of the flow of multiple reagents on paper to perform complex, multi-step biochemical assays in a low-cost, disposable dipstick test format. The assays can be created simply by imprinting flow paths and delay gates on paper. Through careful selection of the ink properties, it is possible to hold the flow of liquids at designated locations on the paper for seconds or even up to a day, offering the flexibility to design a wide range of assays.
This convenient device can be used for various diagnostic applications without the need for bulky, expensive equipment or human intervention. Specifically, it was designed to provide automated signal amplification in lateral flow assays (LFAs)—diagnostic devices used to detect the presence or absence of a target substance, such as a pregnancy test. It was also developed to facilitate automated DNA purification from blood, saliva, and urine samples in point-of-care and resource-limited settings.
Finally, the technology has been used to develop a polymerase chain reaction (PCR) COVID-19 and flu saliva test. This test can detect and amplify viral RNA from SARS-CoV-2 and influenza A & B viruses within the same platform for a multiplexed readout.
- Sophisticated: Provides rapid results for multistep analyses.
- Low cost: Functions without the need for costly equipment or specially trained personnel—a challenge of conventional microfluidic devices
- Predictable: Includes a mathematical model to guide the design of various flow sequences and timing
- Clinical analytical assays, including tests for COVID-19 and the flu
- Pathogen detection
- Biotechnology research
The standard platform for point-of-care (POC) testing in resource-limited settings has long been the lateral flow assays (LFAs) because they are affordable, straightforward, and fast. Though they are compatible with a variety of biological samples including blood, saliva, and urine, they are less prudent in performing multiplexed assays and less sensitive in detecting various analytes of clinical importance. Spontaneous capillary flow in LFAs hinders the execution of multi-step bioassays that require the timely application of different reagents or buffers in multiple steps. To overcome these limitations of LFAs, this device offers a simple mechanism for integrating capillary flow control into an LFA using a low-cost fabrication technique.
To see more technologies like this by Dr. Sarioglu and his team, please click here.