All-new digital technology intended to replace 50-year PCR testing for multiple infections, including COVID variants.

Electronic nanosensors developed in partnership at Purdue University are intended to disrupt the billion-dollar diagnostics industry.

Test Cartridges for Multiple Pathogens

How is Check4™ different from other pathogen tests?

Check4™ intends to be a highly accurate, over-the-counter self-test that is fast, accurate, and affordable. It detects early and asymptomatic infections with the accuracy of a PCR test, but without all the necessary reagents, machines, people, and delays.

It is not an inaccurate antigen test. This electronic-based technology intends to use newly developed nanosensors, saliva, and a user’s smartphone to disrupt the way testing is done now, and into the future.

Fast & Accurate Saliva Self-Test

Created in partnership with Purdue University

Up to 85% more affordable

Results displayed
in minutes

iOS & Android

Protected by
5 patents

Fast & Accurate Saliva Self-Test

Created in partnership with Purdue University

All New Nanosensor Technology

Results Available
in Minutes

iOS & Android

Protected by
5 Patents

woman on phone wearing a covid-19 mask
woman on phone wearing a covid-19 mask

Multiplex Testing

IdentifySensors Biologics and some of the world’s leading researchers at Purdue University have developed a new and disruptive nanosensor technology that rapidly detects COVID-19 and the multiple variants, and intends to develop multiplexed tests as well for influenza. Other intended pathogens include mumps, measles, MRSA, Hep C & B, HIV, foodborne pathogens, and more.

woman on phone wearing a covid-19 mask

Over The Counter Accuracy

The Check4™ platform is the technological breakthrough that will soon move medical testing beyond antiquated chemistry and into the digital era. Current chemical reaction tests will be replaced by fast and affordable digital nanosensors that connect easily to a smartphone, so people will be able to test themselves daily, even on the go if needed or required, and have accurate results within minutes.

Soon, consumers and businesses will have an over-the-counter electronic device in their medicine cabinets. The benefits of an accurate over-the-counter testing device include immediate results without a doctor’s visit or prescription, easy over-the-counter access, more frequent testing, earlier detection, lower costs, reduced transmission rates, and improved population health.

woman on phone wearing a covid-19 mask
woman on phone wearing a covid-19 mask

Results In Hand

To use the test, download the smartphone app and complete the form. Simply place saliva into the reader. Minutes later, the test intends to show results on the smartphone app. That’s it. It was developed so the reader can be used multiple times, by multiple people utilizing different cartridges for different infections.



A highly accurate and affordable over the counter COVID self-test for smartphone


Check4™ — a portable self-test intended to be as accurate as a PCR test in minutes without a prescription. A nanosensor cartridge interacts with saliva to produce a distinguishable electronic signal for positive or negative results with accuracy that rivals PCR tests. Results are displayed in minutes on a smartphone app, which automatically notifies health authorities.


Check4™ is intended to meet the gold-standard in COVID testing with minimal false positives and false negatives. The test is in the final stages of development at Purdue University by world-renowned scientists. It is intended to avoid the limitations of current molecular tests such as enzymatic reactions, amplification, sample preservation or sample transportation, which can introduce artifacts and raise the risk of false positives.


Check4™ is anticipated to cost less than $25 per test, which is six times less expensive than the average cost of a PCR test. This approach avoids costly elements used by laboratory-based molecular tests such as enzymes and reagents that are in short supply. It also eliminates the need for laboratory technicians, diagnostic machines and personal protective equipment.


New nanosensor technology intends to disrupt the medical diagnostics industry by enabling consumers, businesses and governments to perform accurate, over-the-counter testing for a multitude of infections, anywhere, any time.

How does Check4™ work?

A user buys or receives a reusable reader and downloads the free smartphone app. Single-use test cartridges can be purchased as well, for infections such as COVID-19, COVID variants, influenza and other pathogens. A saliva sample is placed in the cartridge and signals are sent to the reader for processing. Test results are transmitted to a smartphone app within minutes, anywhere, anytime. The test intends to be as accurate as PCR tests, but without cost and logistical barriers.

Results Appear in Minutes on Your Smartphone – anywhere, anytime:

  • No nasal swabs
  • No delayed results
  • No prescriptions
  • No doctor visits
  • No laboratories
  • No chemical enhancements or reagents
  • No waiting in lines
  • No mailing in samples
  • No high costs

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