Sibo Zhao,Dan Xiu,Min Zhang,Yao Wang,Miao Qiu,Christopher D. Snow,Yanxin Wang,Laurence A. Belfiore,Jianguo Tang
In this study, a highly sensitive anticancer drug sensor was synthesized using DNA crystals loaded with luminescent Ln 3+ (Eu 3+ /Tb 3+ ) complexes. The sensors exhibited a pronounced color transformation property due to the differential quenching of Eu 3+ and Tb 3+ emissions upon drug interactions. These luminescent hybrid DNA crystals present a significant advancement in sensing anticancer drugs like curcumin, transitioning from monitoring fluorescence intensity changes to a visually discernable color change. This new approach eliminates the need for specialized instrumentation. Owing to the intrinsic biocompatibility of materials composed of DNA, this hybrid sensor has the potential to sense drugs within the human body. Hybrid crystals loaded with a single complex will lose their fluorescence properties due to drug quenching; however, crystals loaded with mixed complexes emit distinct fluorescent colors, such as yellow-green and orange-red, at different drug concentrations. This color transformation allows for the direct determination of drug concentration based on crystal color, making the sensing process more simple and easily observable.
We present herein an easy way to prepare novel responsive hydrogels by simply doping lanthanide complexes into a polymer hydrogel, poly(2-acrylamido-2-methyl-1-propanesulfonicacid) (PAMPSA). The resulting hybrid hydrogels can be readily processed into a range of shapes. Both the on–off luminescence switching and the healable properties are simultaneously achieved in the resulting responsive hybrid hydrogels. They exhibit effectively self-healing performance without any external stimulus and reversible “on–off” luminescence switching triggered by exposure to acid–base vapor. The key to this on–off luminescence switching behavior is that the protonation of the organic ligands compete with full coordination to Ln3+ and that incomplete coordination affects the luminescence yield. The high proton strength in the resulting hydrogels makes the doped lanthanide complexes unstable, and ammonia (or triethylamine) vapor can dramatically decrease the proton strength through neutralization, driving the full coordination of the ligand to Ln3+.