Researchers in Australia have developed a nanosensor that can detect the onset of gestational diabetes with 95% accuracy. Demonstrated by a team led by Carlos Salomon at the University of Queensland, the superparamagnetic “nanoflower” sensor could enable doctors to detect a variety of complications in the early stages of pregnancy.
Many complications in pregnancy can have profound and lasting effects on both the mother and the developing foetus. Today, these conditions are detected using methods such as blood tests, ultrasound screening and blood pressure monitoring. In many cases, however, their sensitivity is severely limited in the earliest stages of pregnancy.
“Currently, most pregnancy complications cannot be identified until the second or third trimester, which means it can sometimes be too late for effective intervention,” Salomon explains.
To tackle this challenge, Salomon and his colleagues are investigating the use of specially engineered nanoparticles to isolate and detect biomarkers in the blood associated with complications in early pregnancy. Specifically, they aim to detect the protein molecules carried by extracellular vesicles (EVs) – tiny, membrane-bound particles released by the placenta, which play a crucial role in cell signalling.
In their previous research, the team pioneered the development of superparamagnetic nanostructures that selectively bind to specific EV biomarkers. Superparamagnetism occurs specifically in small, ferromagnetic nanoparticles, causing their magnetization to randomly flip direction under the influence of temperature. When proteins are bound to the surfaces of these nanostructures, their magnetic responses are altered detectably, providing the team with a reliable EV sensor.
“This technology has been developed using nanomaterials to detect biomarkers at low concentrations,” explains co-author Mostafa Masud. “This is what makes our technology more sensitive than current testing methods, and why it can pick up potential pregnancy complications much earlier.”
Previous versions of the sensor used porous nanocubes that efficiently captured EVs carrying a key placental protein named PLAP. By detecting unusual levels of PLAP in the blood of pregnant women, this approach enabled the researchers to detect complications far more easily than with existing techniques. However, the method generally required detection times lasting several hours, making it unsuitable for on-site screening.
In their latest study, reported in Science Advances, Salomon’s team started with a deeper analysis of the EV proteins carried by these blood samples. Through advanced computer modelling, they discovered that complications can be linked to changes in the relative abundance of PLAP and another placental protein, CD9.
Based on these findings, they developed a new superparamagnetic nanosensor capable of detecting both biomarkers simultaneously. Their design features flower-shaped nanostructures made of nickel ferrite, which were embedded into specialized testing strips to boost their sensitivity even further.
Using this sensor, the researchers collected blood samples from 201 pregnant women at 11 to 13 weeks’ gestation. “We detected possible complications, such as preterm birth, gestational diabetes and preeclampsia, which is high blood pressure during pregnancy,” Salomon describes. For gestational diabetes, the sensor demonstrated 95% sensitivity in identifying at-risk cases, and 100% specificity in ruling out healthy cases.
Based on these results, the researchers are hopeful that further refinements to their nanoflower sensor could lead to a new generation of EV protein detectors, enabling the early diagnosis of a wide range of pregnancy complications.
“With this technology, pregnant women will be able to seek medical intervention much earlier,” Salomon says. “This has the potential to revolutionize risk assessment and improve clinical decision-making in obstetric care.”
