An iridium(III) complex/G-quadruplex ensemble for detection of ochratoxin A based on long-lifetime luminescent.

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.

Real-time detection of oxalyl chloride based on a long-lived iridium(iii) probe.

A series of luminescent iridium(iii) complexes were designed and evaluated for their ability to detect oxalyl chloride ((COCl)2) at ambient temperature. In the presence of (COCl)2, a double amidation reaction takes place at the diamino functionality of complex 1, leading to the switching-on of a long-lived red luminescence with a 9-fold enhanced emission. Complex 1 exhibited high sensitivity and selectivity, with a detection limit for (COCl)2 at 32 nM. Additionally, complex 1 can be used to detect (COCl)2 using a simple smartphone, allowing for the portable and real-time monitoring of (COCl)2.