Portable System Allows for Inexpensive Diagnosis of HIV-HCV Coinfection

A portable paper device has recently been developed for point-of-care diagnosis of HIV and hepatitis C virus (HCV) coinfections within serum samples.

Experts estimate that one-third of people with HIV and AIDS are coinfected with HCV. While rapid point-of-care tests are commercially available, they are often inaccurate and unaffordable.

Researchers published a paper in Biomicrofluidics that describes the design and testing process of a portable, paper-based electrochemical platform with multiplexing and telemedicine capabilities.

During the study, researchers used spiked mouse serum samples to assess the sensitivity of the new device. The results of the study revealed detectable HIV and HCV antibodies at 300 picograms per mL and 705 picograms per mL, respectively.

These values proved to be lower than those of current antibody tests.

The biggest advantage for this device is its ability to run 8 tests for HIV and HCV simultaneously, with a 20-minute timeframe that’s both highly accurate and sensitive. Additionally, being able to take the platform anywhere is helpful in the HIV and HCV fight.

“Our experimental setup consists of a paper device with 8 electrochemical biosensors — for handy, one-time, disposable use – and a custom-made, handheld electrochemical reader, or potentiostat, to keep costs as low as possible,” said researcher Xinyu Liu.

In order for a test to be run, the paper device is inserted into a slot on the potentiostat. Microliter drops of serum samples and reagents are then added to each biosensor. To trigger the electrochemical measurements, a simple button is pushed.

Additionally, the device is compatible with existing internet-based and mobile network-based e-health systems. The data taken from the test can be directly displayed on an LCD screen of the potentiostat or transmitted to a smartphone or personal computer, and then to a centralized laboratory or hospital through the mobile network or internet remote diagnoses.

When researchers explored the potential cross-reaction between the HIV and HCV antibody tests, they found that there was no significant interference of the 2 tests.

“These results demonstrate that our diagnostic platform shows great potential for diagnosing HIV/HCV coinfections in real patient samples,” Liu said.

Since the electrochemical detection is widely applicable to different types of biomolecules, researchers state that it could be readily extended to detect other disease markers like ions, metabolites, nucleic acids, and proteins.

“We'll explore the stability of the paper device during long-term storage, and then begin real patient sample testing in Canada and Kenya,” Liu said. “Our long-term goal is to further extend the functionality of this diagnostic platform by targeting other molecular disease markers.”