Fast and Inexpensive Nanotechnology Zika Test Announced

Washington University researchers have developed a test that quickly detects the presence of Zika virus in blood.

This test uses gold nanorods mounted on paper to detect Zika infection within a few minutes.

Current tests for the Zika virus require that a blood sample be refrigerated and shipped to a laboratory, which delays the diagnosis.

Moreover, the samples for this new Zika test do not require refrigeration.

Researchers from the Washington University School of Medicine and the School of Engineering & Applied Science said in a press release, “Many people infected with Zika don't know they're infected.”

“Testing is particularly important for pregnant women because Zika infection can cause congenital Zika syndrome, which contributes to several neurologic problems in the fetus or newborn infant.”

Evan D. Kharasch, MD, PhD, one of the study's investigators said, "The most effective way to diagnose the Zika disease is not to wait for people to develop symptoms but to do population screening."

The test relies on a protein made by Zika virus that causes an immune response in infected individuals. The protein is attached to tiny gold nanorods mounted on a piece of paper. The paper then is completely covered with tiny, protective nanocrystals. The nanocrystals allow the diagnostic nanorods to be shipped and stored without refrigeration prior to use.

To use the test, a technician rinses the paper with slightly acidic water, removing the protective crystals and exposing the protein mounted on the nanorods. Then, a drop of the patient's blood is applied.

If the patient has come into contact with the virus, the blood will contain immunoglobulins, that react with the protein.

"With this test, results will be clear before the patient leaves the clinic, allowing immediate counseling and access to treatment," said these researchers.

The researchers estimate that the cost of the gold used in one of the assays would be 10 to 15 cents.

Most people infected with Zika do not experience symptoms or will only have mild effects, including fever, rash, headache, joint and muscle pain and red eyes, according to the Centers for Disease Control and Prevention (CDC).

According to CDC guidance, healthcare providers should screen all pregnant women in the US for possible Zika exposure and symptoms at each prenatal care visit.

This work was supported by the National Science Foundation, grant numbers CBET1254399 and CBET1512043. Additional funding was provided by the Department of Anesthesiology, Washington University School of Medicine in St. Louis and the Department of Mechanical Engineering & Materials Science, Washington University in St. Louis.

These researchers did not disclose any conflicts of interest:  Q. Jiang, Y. J. Chandar, S. Cao, E. D. Kharasch, S. Singamaneni, J. J. Morrissey, Adv. Biosys. 2017, 1700096.