RMIT University
Melbourne, Australia
www.rmit.edu.au

When you’re working with a fluid as hypersensitive as blood, it pays to have specialists on board.

“Blood isn’t straightforward. It’s very sensitive to artificial surfaces so it will stick like crazy to things; you get clotting all over the place,” says RMIT biochemist Warwick Nesbitt, PhD.

Nesbitt and his team at RMIT’s Micro Nano Research Facility (MNRF) and the Australian Centre for Blood Diseases are at the crossroads of engineering and biomedical science.

Their aim? To miniaturize the complex blood-handling features of a pathology lab onto a tiny chip, the size of a postage stamp.

Along with researchers at Monash University and the University of Melbourne and clinicians at the Alfred Hospital’s Department of Clinical Haematology, the team has successfully developed new microfluidic technologies that are being used in a myriad of ways to help solve clinical challenges in haematology.

These technologies range from more accurate diagnostic tools for blood disorders to improving our understanding of how platelets work and developing devices that can slash the time it takes to verify if someone has suffered a heart attack.

The work was recently boosted with a $657,000 grant from the National Health and Medical Research Council to support the development of a microfluidic platelet analyzer that can indicate whether blood clots effectively.

Everyday Pathology

The microfluidic chips being developed by the team contain tiny channels, pumps, valves, and processors, enabling precise and flexible manipulation of fluids.

The chips are fast, portable, and able to handle vast quantities of tiny processing elements. Importantly, they are also cost-effective to produce and can be easily mass manufactured.

The complex features of a pathology lab, in miniature. (Credit: RMIT)

When combined with a highly sensitive photonic sensor for biochemical analysis, the technology effectively becomes a miniature laboratory — a lab-on-a-chip — but one that needs no specialist training to use.

“Because whole blood is so complex, most blood diagnostic tests tend to involve some form of processing, such as spinning out red blood cells,” Nesbitt says.

“Pathology lab tests are technically demanding and expensive. You need a highly trained medical scientist that is experienced in blood separation techniques and analysis to ensure consistency of results.

“Our ultimate aim is to make lab-on-achip devices that an unskilled operator can use, that can either do the processing inside the device or work with blood taken straight from patients.

“This is particularly important for regional areas, where emergency clinics with no in-house pathology services can face long delays in waiting for results.”

Precision and Reliability

Nesbitt and the team at the MNRF develop micro devices that can be used for three key aspects of blood: bleeding, clotting, and detecting biomarkers.

The researchers have worked on the diagnosis and monitoring of the most common genetic bleeding disorder, Von Willebrand disease (VWD).

The current testing of VWD involves laboratory-based assays along with clinical assessment. In addition, certain forms of the disease can be difficult to diagnose.

Invisible to the naked eye, the tiny channels and pumps in a microfluidic chip can precisely and rapidly manipulate fluids. (Credit: RMIT)

The RMIT team’s proof-of-concept trial showed their tailored micro device could detect the particular forms of the disease that are most difficult to spot with standard tests. Invisible to the naked eye, the tiny channels and pumps in a microfluidic chip can precisely and rapidly manipulate fluids.

In the future, the team is hoping to use the same device to detect changes in the way platelets function in people with diabetes, metabolic syndrome, and acute coronary syndrome; conditions that make patients prone to platelet-dependent cardiovascular diseases. The researchers have also had promising early results in the development of a device to sensitively detect cardiac troponin, a clinical biomarker for heart attacks.

“Clinicians test blood for troponin when a patient comes into emergency suffering signs of heart attack, but it can take some time for results to come back from pathology,” Nesbitt says.

“There are faster bedside tests on the market but they’re not always reliable and there is a push for more reliable point-of-care tests.

“We’re working on a point-of-care device that brings together a sensitive photonic sensor and a microfluidic system to give reliable results in minutes.”

This article was written by Gosia Kaszubska. For more information, visit here .