@misc{10481/111408,
year = {2026},
month = {5},
url = {https://hdl.handle.net/10481/111408},
abstract = {Urea is a crucial biomarker in clinical analysis, mainly used to diagnose and monitor kidney condition. However, its reliable determination in serum in point-of-care testing format still remains a vital challenge. Here, we tackled this issue by developing a microfluidic thread-based optical biosensor for serum urea determination. The working principle of the presented device was combining enzymatic urea hydrolysis using urease with the resulting ammonium ions detection using ionophore-chromoionophore chemistry. Urease was immobilized on thread with the aid of synthesized urease-calcium phosphate nanoflowers while components for ammonium ions detection were embedded in PVC-based membrane located on the same thread. In the first step, ammonium ions determination in a thread-based sensor was optimized. Then, urease-calcium posphate nanoflowers (U-CaNFs) were included on the thread to ensure selectivity for urea. U-CaNFs synthesis was optimized and the resulting nanoflowers were characterized using various analytical techniqes (e.g. SEM, EDS, TGA, XRD). The calculated limit of detection for urea was 37 µmol L−1 and the total analysis time was only 8 min. The developed thread-based devices were validated with control sera samples, proving their high accuracy.},
organization = {IL was supported by the Foundation for Polish Science (FNP). This research was funded by Spanish MCIN/AEI/10.13039/501100011033/with project PID2022–138727OB-I00. The project was partially supported by European Regional Development Funds “ERDF A way of making Europe”. Junta de Andalucía project DGP_PIDI_2024_01237. Funding for open access charge: Universidad de Granada / CBUA.},
keywords = {Urea},
keywords = {Microfluidic thread-based analytical device},
keywords = {Nanoflowers},
keywords = {Ionophore-based optical sensor},
title = {Thread-based colorimetric biosensor for urea determination in serum},
doi = {https://doi.org/10.1016/j.snb.2026.139644},
author = {Lewinska, Izabela and Bącal, Paweł and Orbe Payá, Ignacio De and Capitán Vallvey, Luis Fermín and Erenas Rodríguez, Miguel María},
}