101973-09-5Relevant articles and documents
Target-activated coumarin phototriggers specifically switch on fluorescence and photocleavage upon bonding to thiol-bearing protein
Lin, Qiuning,Bao, Chunyan,Cheng, Shuiyu,Yang, Yunlong,Ji, Wei,Zhu, Linyong
, p. 5052 - 5055 (2012)
A new concept in which only the molecular target, such as a thiol-bearing protein, can activate the phototrigger has been demonstrated. Such target-activatable phototriggers comprise three parts: a 7-aminocoumarin phototrigger, an electron acceptor (maleimide) that efficiently quenches the coumarin excited state, and a caged leaving group attached to the coumarin. In the absence of mercaptans, photoinduced electron transfer between coumarin and maleimide effectively blocks both the fluorescence and photocleavage pathways. Thiol-bearing molecules, however, readily annihilate the electron acceptor and thus restore the phototrigger for photorelease of the caged cargo (e.g., biotin). Unlike traditional phototriggers, functional-group-activated phototriggers allow easy handling under ambient light, report specific bonding to the target, and enable photocleavage capability selectively at the binding site in situ, thus effectively positioning the photoreleased cargo at the target. Meanwhile, the unique feature of thiol-specific activation of the fluorescence and photocleavage make our new phototrigger a universal tool that can be used to identify accurately protein cysteine S-nitrosylation, a physiologically important posttranslational modification.
7-Amino coumarin based fluorescent phototriggers coupled with nano/bio-conjugated bonds: Synthesis, labeling and photorelease
Lin, Qiuning,Bao, Chunyan,Fan, Guanshui,Cheng, Shuiyu,Liu, Hui,Liu, Zhenzhen,Zhu, Linyong
, p. 6680 - 6688 (2012/07/28)
By several synthetic pathways, we designed and synthesized a new series of unsymmetrical substituted 7-amino coumarin-based phototriggers with various nano/bio-conjugated bonds. The photophysical properties of most of the substituted coumarin-based phototriggers, except for compound P9 with maleimide group, showed no significant change compared with that of 7-(diethylamino)-4- (hydroxylmethyl) coumarin (DEACM-OH, the reported symmetric substituted 7-amine coumarin based phototrigger). Four compounds (P2, P4, P9, 14) were successfully conjugated with typical carriers such as mesoporous silica nanoparticles, biocompatible polymer PEG and common protein BSA, respectively. The efficient photorelease of ibuprofen (IBU) in the model cargo delivery system of MD4 confirmed that our designed phototriggers could serve well as a photo-cage for bioactive molecules and the release can be regulated precisely by manipulating the external irradiation conditions. All the results hinted at the superiority of using these coumarin functional compounds for photo-regulated release in biotechnology and biomedical areas. The Royal Society of Chemistry 2012.