Digital Diagnostics
on Graphene

Detecting multiple pathogens simultaneously without enzymes, amplification or reagents

Check4® by IdentifySensors Biologics® is a next-generation digital diagnostic platform intended to detect multiple pathogens within 5 minutes at the gene level. The platform eliminates the need for enzymatic amplification and reagents. Graphene sensor technology has moved diagnostics beyond chemical testing into a rapid digital platform as accurate as a PCR test but significantly more sensitive and cost effective. 

Printed graphene sensors isolate targeted viruses and bacteria from saliva and other bodily fluids within a handheld, Bluetooth device. The platform is intended to detect the genetic material of dozens of pathogens for over-the-counter and point-of-care use.

With a target price at a fraction of current molecular tests, Check4® is intended to disrupt the PCR market for many infections. Future plans for the platform include rapidly detecting biomarkers and T-cell immunity, in conjunction with direct diagnosis to help clinicians predict infection severity and vaccine effectiveness among individual patients.

Facts at a Glance

Graphene sensors rapidly detect infections digitally from saliva

Breakthrough technology that is not PCR or antigen

No enzymes, amplification, reagents or lab work

Ultra-high accuracy and sensitivity from saliva and other bodily fluids

Targeted at half the price of PCR tests

Multiplex tests for multiple infections simultaneously

Test in less than five minutes

Results sent to smartphones, remote dashboard or a clinical database

Plans to functionalize for direct diagnosis, biomarkers and T-cell immunity

Data capturing for infectious diseases

How It Works


Step One

Patients and other end-users deposit a small saliva sample into the Check4® device, which is about the size of a cell phone. If targeted DNA or RNA is present in saliva, digital signals passing through the graphene sensors trigger a molecular reaction and a cloud-based algorithm determines the results. If the targeted pathogen is absent in the saliva, a molecular reaction cannot occur, and the test is deemed negative. Future plans include the ability to test through other bodily fluids.


Step Two

The reactions among the genetic material are unmistakable. The algorithm verifies the data and sends results to a user’s cell phone or to a clinical database in minutes. These sensors use no chemical additives and can be easily functionalized by the manufacturer for COVID, Flu, RSV and a host of other infections, including HIV, Lyme and hepatitis.


Dubbed a miracle material by renowned researcher, Dharani Sabba, graphene is comprised of a single layer of carbon atoms in a honeycomb configuration that makes it the thinnest, strongest and most conductive material in the world.

This super-conductor is dramatically changing the fields of super conductors, electrical transmission, energy generation, batteries and sensors. Scientists at IdentifySensors® have developed a graphene application that triggers a reaction within genetic material when it interacts with a specific electrical signature.

A small graphene surface, millimeters wide, serves as the sensor inside Check4® test cartridges. When sensors are functionalized to detect targeted RNA or DNA, such as the COVID virus, the molecular reactions that diagnose an infection are instantly identifiable in a highly precise and effective digital application.  


The Check4® testing platform comes is two main parts: 1) A reader, which connects to a user’s cell phone or to a clinical database; and 2) Single-use test cartridges, which can contain multiple graphene sensors to detect multiple infections.

The reader, which can be reused thousands of times, serves as the base of the platform, accepting any number of test cartridges. Disposable test cartridges, which require the reader to work, will be sold separately. Pricing for the full platform is intended to fall well below current molecular tests, such as PCR.

Reusable reader

Disposable test cartridges


Clinical tests used to determine the effectiveness of the Check4® platform for COVID were recently performed on samples from sick patients at the Indiana Medical Center. Each sample was verified positive or negative using PCR tests. IdentifySensors researchers working at Purdue University then diluted the saliva down to 200 gene copies per milliliter. The Check4 platform performed with 99.9 percent test accuracy on the diluted samples.

A typical PCR test detects infections down to about 900 gene copies per milliliter (limit of detection), making the Check4 graphene sensor more than four times more sensitive than PCR tests without amplification. This groundbreaking limit of detection enables highly accurate diagnosis well before patients show symptoms and helps slow the spread of disease.


The Check4® testing platform detects pathogens digitally, enabling test results to be monitored remotely on a mobile device, a clinical database or an organization’s dashboard. Patients can test at home, while clinicians see results in real time, remotely and without risking infection or spreading.

Businesses, events and other gatherings can test attendees remotely before clearing for entry, such as on a cruise ship. Health care agencies can access population health data for infection control and monitoring.

Businesses and point-of-care organizations can monitor test results remotely

Health organizations can access extensive population health data


IdentifySensors Biologics® has begun working with the FDA in a pre-submission process with plans to seek approvals in 2023. The company is preparing for FDA approval routes, which include De Novo Classification and/or a 510(k) pathway.


IdentifySensors® holds seven issued patents, with ten more pending, all of which cover multiple aspects of the graphene sensor and methods used to prepare, detect, digitize and communicate the presence of pathogens with DNA or RNA.

Seven issued patents

Ten pending patents


IdentifySensors Biologics® has developed its Check4® testing platform for two principal markets: over-the-counter sales and point-of-care use in clinical environments. The company plans to roll out product in 2023. 

  • Point of care 
  • Over-the-counter


Researchers and public health agencies have long sought an ideal testing platform: a comprehensive technology that performs three critical functions simultaneously: 1) rapid multiplex detection; 2) identifying specific biomarkers that predict illness severity and; 3) T-Cell detection that measures a patient’s response to vaccines.

Obtaining this breadth of information from a single sample of saliva or other bodily fluid, performed at home and monitored remotely, could dramatically change the future of digital molecular diagnostics.   

Graphene sensors developed by IdentifySensors Biologics® have the potential to reach these major milestones. The company is currently focused on the first stage of detection – direct multiplex pathogen diagnosis – but a longer vision could have a profound impact on individual and population health.