Researchers have developed a new approach for the rapid detection of multiple disease pathogens in a single test, with a method from the biomedical frontline: ‘decoding’ tunable photonic nanocrystals.

A demonstration successfully detected some of the world’s deadliest conditions –trace amounts of DNAs from HIV, Human Papillomavirus 16, Ebola virus, and Hepatitis B virus – simultaneously in a single test within minutes, requiring only a tiny sample.

The breakthrough follows the researchers’ earlier success in demonstrating the cutting-edge technology of tunable photonic nanocrystals, or “τ-Dots”, which can be coded in the time domain (‘Tunable lifetime multiplexing using luminescent nanocrystals’ Nature Photonics 2013).

The team has now found the other half of the puzzle – decoding the lifetime codes with high-speed scanning that can precisely determine the τ-Dots’ luminescent decay times to the microsecond.

“This method offers untapped biomedical potential in high-speed detection of pathogens, early-stage cancer diagnosis, and bioinformatic analysis towards personalised medicine,” said lead researcher Dr Yiqing Lu, Macquarie University.

“Our method recognises the difference in the lifetimes, just as people can check the colours of luminescent objects. We now are able to build a huge library of lifetime-colour coded microspheres, to perform multiple medical tasks or diagnoses at the same time.

“The time saved by omitting the need to grow or amplify a culture sample for testing, and eliminating the need to run multiple tests, will save future patients precious time so treatment can begin, which can be life-saving when managing aggressive disease states like meningococcal.”

ARC Future Fellow Associate Professor Dayong Jin said the method is also a significant step toward personalised medicine.

“Individuals’ genetic signatures are often behind the frequent failures of traditional symptom-diagnostics. The new toolkit will enable personalised diagnosis of individual’s genetic makeup, so that individually targeted therapies can be specifically tailored according to their decoded gene expression profile.”

Co-author, Professor J Paul Robinson from Purdue University said “This toolset is really a paradigm shift for identifying disease molecules in high-noise environments typical in biological systems such as cancer detection, high throughput screening and also in the bio detection domain.”

Although a working prototype has been developed, the project team are seeking commercial partners to assist with the verification of clinical efficacy followed by product development. This could see the new medical offering widely available in hospitals, pathology labs, and GP clinics.

The project has been the work of an international collaboration funded by an ARC Discovery Grant led by the former Macquarie Deputy Vice-Chancellor (Research) Professor Jim Piper, A/Prof. Jin at the Advanced Cytometry Labs, Dr. Robert Leif at Newport Instruments and Prof. J. Paul Robinson at Purdue University Cytometry Labs in USA.

The paper “On-the-fly decoding luminescence lifetimes in the microsecond region fort he lanthanide-encoded suspension arrays” has been published by Nature Communications.

Filed under: Featured Science & nature