The findings, published in Analytical Chemistry, offer a new technological approach for the early diagnosis of jaundice.
Jaundice is a critical health issue in neonates, affecting 60% of newborns and contributing to early neonatal mortality. Elevated free bilirubin levels indicate jaundice, with healthy levels ranging from 1.7 μM to 10.2 μM in healthy individuals. Concentrations below 32 μM typically don't show classic symptoms. Rapid and accurate detection of bilirubin in neonates is critical. UCNPs show great potential for detecting small molecules in biological samples due to minimal background fluorescence interference. However, their low luminescence intensity limits their effectiveness, highlighting the need for UCNP probes with higher emission intensity for bilirubin detection.
To overcome this limitation, the researchers employed a zinc ion doping strategy to regulate the growth of upconversion nanocrystals, improving the energy transfer efficiency of the nanoparticles, thus achieving efficient, high-intensity upconversion luminescence.
Furthermore, a 980 nm near-infrared excited upconversion visual sensing platform for serum bilirubin detection was developed. By combining UCNPs with sulfosalicylic acid and iron ions to form an efficient upconversion nanoprobe, fluorescence and colorimetric gradient changes were observed in the presence of bilirubin, enabling precise detection of bilirubin.
In addition, the researchers constructed a portable sensing platform using 3D printing technology. When combined with a smartphone's color recognition function, this device provides a rapid and convenient clinical testing solution for bilirubin monitoring.
The study demonstrates that the sensor's fluorescence mode achieves a detection limit as low as 21.4 nM, enabling accurate bilirubin detection in complex biological matrices.
This study shows strong upconversion luminescence emission and highlights the potential for early disease diagnosis through highly sensitive biomarker detection.
Read the original article on Chinese Academy of Sciences (CAS).