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Updated: Jan 23, 2026

IridiumIII Luminescent Probe for Detection of the Malarial Protein Biomarker Histidine Rich Protein-II
Published on: July 7, 2015
An iridium(III) complex/G-quadruplex ensemble for detection of ochratoxin A based on long-lifetime luminescent
Jia-Tong Zhang1, Tian-Shu Kang1, Suk-Yu Wong2
1State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, 999078, Macao.
Abstract:
A G-quadruplex-based platform has been developed for the time-resolved monitoring of ochratoxin A (OTA). The simple platform displays good sensitivity for OTA with a detection limit of 40 nM via steady-state emission spectroscopy. Notably, the platform showed a detection limit of 10.8 nM via time-resolved emission spectroscopy (TRES), which is about 4 times more sensitive than steady-state mode. Moreover, the probe showed excellent selectivity for OTA over other mycotoxins. Furthermore, OTA was successfully detected in actual herbal plant extracts samples. Our platform is the first to detect OTA using TRES to distinguish between the target signals versus the auto-fluorescence of real samples. This platform shows improved detection speed, accuracy and sensitivity with simple operation, low cost, and no requirement for complicated pre-processing.
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