Stimulus Response of TPE-TS@Eu/GMP ICPs: Toward Colorimetric Sensing of an Anthrax Biomarker with Double Ratiometric Fluorescence and Its Coffee Ring Test Kit for Point-of-Use Application

Abstract

In this work, by fully exploring the stimulus response of infinite coordination polymer nanoparticles (ICPs) and by taking advantage of the particular optical properties of ICP guest tetra­(4-sulfophenyl)­ethene (TPE-TS) with adjustable monomer emission (ME) and aggregation-induced emission (AIE), we demonstrated a novel sensing mechanism for an anthrax biomarker dipicolinic acid (DPA) based on the competitive coordination interaction regulating the structure of TPE-TS@Eu/GMP ICPs. The double ratiometric fluorescence stemmed from triple response of TPE-TS@Eu/GMP ICPs without spectral cross-interference (ME and AIE from TPE-TS and sensitized emission from Eu/DPA) and a corresponding blue-to-red fluorescent color change, which not only benefited the direct detection of DPA with high sensitivity and selectivity, but also offered a great opportunity to realize real-time monitoring of DPA released by Bacillus subtilis spores. Furthermore, the coffee ring deposition patterns on a test paper were innovatively tuned by the quantity and morphology changes of TPE-TS@Eu/GMP ICPs during their stimulus response toward DPA, which could be exploited as expanded signal channels. By integrating a multichannel responsive coffee ring test kit with image recognition and processing application installed on smartphones, point-of-use analysis of DPA could be realized in a low-cost and high-throughput fashion.

A portable visual coffee ring based on carbon dot sensitized lanthanide complex coordination to detect bisphenol A in water

“…The changes above suggest that Eu 3+ had been coordinated with AMP, and the CDs@Eu–AMP nanocomposites had been successfully synthesized. 50 The infrared spectra of CDs@Eu–AMP-BPA showed two strong peaks at 1580 cm −1 and 3404 cm −1 , respectively, and there was no C O peak at 1705 cm −1 , which might overlap with the peak at 1580 cm −1 , indicating that hydrogen bonds were formed between CDs and OH groups of BPA. The formation of hydrogen bonds causes the shift of the C O adsorption band from high to low frequencies.…”

“…The formation of hydrogen bonds causes the shift of the C O adsorption band from high to low frequencies. 50 …”

“…Eu–AMP nanocomposites were synthesized according to the method reported elsewhere. 50 Briefly, 5 mL of Eu(NO 3 ) 3 ·6H 2 O (10 mM) aqueous solution was added into 5 mL of Tris buffer solution (0.1 M, pH 7.4) containing AMP (10 mM), mixed and reacted for 1 h at room temperature with vigorous stirring. Then, the white precipitates were centrifuged at a speed of 8000 rpm for 5 min and washed with ultrapure water several times, and dried at room temperature for later use.…”

Optical-Based Biosensors and Their Portable Healthcare Devices for Detecting and Monitoring Biomarkers in Body Fluids

“…Following this methodology, evaluating the red/blue ratio will give a quantitative result of the DPA level in the biological sample. The detection limit of this coffee ring sensor was claimed to be 27 nM [ 64 ].…”

Insights on Luminescent Micro‐ and Nanospheres of Infinite Coordination Polymers

“…More recently, the detection of substances using smartphones has been getting increasing attention due to the ease of use and accessibility for remote or domestic locations. Based on luminescence color change, an approach for real-time monitoring of DPA released by B. subtilis spores was reported by Huang et al [99] Eu/GMP ICPs were incorporated with guest tetra(4-sulfophenyl)ethene (TPE-TS), which exhibited both monomer emission (ME) and aggregation-induced emission (AIE). Combined with the sensitized emission from the DPA -Eu 3 + interaction, TPE-TS@Eu/GMP could detect DPA using ratiometric approach (blue-to-red emission).…”