New diagnostic tool detects the first signs of a heart attack within minutes

Researchers at Johns Hopkins University (JHU) have introduced a tiny chip with a unique surface that can quickly and accurately detect blood biomarkers of a heart attack within minutes, far exceeding the speed of current methods, even at very low concentrations. The team behind this device says it could be adapted as a tool for first responders and people at home.

In the critical moments of a heart attack, time is of the essence. The earlier the diagnosis is made, the quicker blood flow to the heart can be restored, minimizing damage and improving patient outcomes. However, heart attacks are accompanied by symptoms that can vary greatly from person to person.

In the high-risk situation of an emergency room, every minute counts when it comes to diagnosing a possible heart attack. Currently, patients must wait one to two hours for results of key blood tests, including creatine kinase and troponin, biomarkers that indicate damage to the heart muscle.

Led by JHU researchers, a new, cutting-edge chip with a breakthrough nanostructured surface has been developed to quickly detect these vital biomarkers in just minutes, even when they are present at very low concentrations.

“Heart attacks require immediate medical intervention to improve patient outcomes. While early diagnosis is crucial, it can also be extremely challenging – and nearly impossible outside of a clinical setting.” said lead author Peng Zheng, a research fellow at Johns Hopkins University. “We were able to invent new technology that can quickly and accurately determine whether someone is having a heart attack.”

The heart of the invention is the “metasurface” of a tiny chip that amplifies electrical and magnetic signals during Raman spectroscopy analysis. First, a single layer of carefully arranged polystyrene beads forms a hexagonal pattern on a quartz substrate. Subsequent deposition of alternating thin layers of gold and silicon fills the gaps between the beads, resulting in the formation of nanoscale, pyramid-like stacks of gold and silicon oxide metaatoms after the beads are removed.

This sophisticated combination of metal (gold) and dielectric (silicon) serves to amplify the chip’s electric and magnetic fields, thereby significantly improving the ability of Raman spectroscopy to analyze the patient’s blood.

Raman spectroscopy, a powerful chemical analysis technique, provides comprehensive information about a substance by using a wide range of laser wavelengths to interact with its chemical bonds.

The chip’s amazing capabilities allowed it to quickly detect heart attack biomarkers, even at extremely low concentrations, within seconds. It was sensitive enough to identify biomarkers earlier than current tests and detect them long before a heart attack.

“We’re talking about speed, we’re talking about accuracy and we’re talking about the ability to take measurements outside of a hospital.” said Barman, a bioengineer in JHU’s Department of Mechanical Engineering. “We hope that in the future this can be turned into a portable instrument like a Star Trek tricorder, where you have a drop of blood and then, voilà, in a few seconds you have the discovery.”

The researchers envision this tool as a home heart attack detector in the future. Not only is it designed to diagnose heart attacks, but it can also be modified to detect infectious diseases and cancer biomarkers, the researchers said.

“There is enormous commercial potential” said the barman. “There is nothing that limits this platform technology.”

The team’s next steps are to further refine the blood test and move into larger clinical trials.

Magazine reference:

1. Peng Zheng, Lintong Wu, Piyush Raj, Jeong Hee Kim, Santosh Kumar Paidi, Steve Semancik, Ishan Barman. Multiplex SERS detection of serum cardiac markers using plasmonic metasurfaces. Advanced Science, 2024; DOI: 10.1002/advs.202405910