title: Chemiluminescence of off-line and on-line gold nanoparticle-catalyzed luminol system in the presence of flavonoid.
abstract: It was found that flavonoids could remarkably inhibit the chemiluminescence (CL) intensity of an off-line gold nanoparticle (AuNP)-catalyzed luminol-H2O2CL system. By contrast, flavonoids enhanced the CL intensity of an on-line AuNP-catalyzed luminol-H2O2CL system. In the off-line system, the AuNPs were prepared beforehand, whereas in the on-line system, AuNPs were produced by on-line mixing of luminol prepared in a buffer solution of NaHCO3- Na2CO3and HAuCl4with no need for the preliminary preparation of AuNPs. The on-line system had prominent advantages over the off-line system, namely a lowering of the background noise and improvements in the stability of the CL system. The results show that differences in the signal suppression effect of flavonoids on the off-line AuNP-catalyzed CL system are influenced by the combined action of a free radical scavenging effect and occupy-sites function; the latter was proved to be predominant using controlled experiments. Enhancement of the on-line system was ascribed to the presence of flavonoids promoting the on-line formation of AuNPs, which better catalyzed the luminol-H2O2CL reaction, and the enhancement activity of the six flavonoids increased with the increase in reducibility. This work broadens the scope of practical applications of an AuNP-catalyzed CL system.
authors.affiliation: Department of Pharmacy, Fuyang People's Hospital, Fuyang, People's Republic of China.
authors.forename: Dong
authors.initials: D
authors.lastname: Wu
authors.affiliation: First  Affiliated  Hospital  of  Anhui  University  of  Chinese  Medicine, Hefei, People's Republic of China.
authors.forename: Xiaoyue
authors.initials: X
authors.lastname: Zhang
authors.affiliation: First  Affiliated  Hospital  of  Anhui  University  of  Chinese  Medicine, Hefei, People's Republic of China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Liu
authors.affiliation: First  Affiliated  Hospital  of  Anhui  University  of  Chinese  Medicine, Hefei, People's Republic of China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Ma
authors.affiliation: Department of Clinical Laboratory, Fuyang Second People's Hospital, Fuyang, People's Republic of China.
authors.forename: Xiaowu
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Pharmacy, Fuyang People's Hospital, Fuyang, People's Republic of China.
authors.forename: Xiaojuan
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Pharmacy, Fuyang People's Hospital, Fuyang, People's Republic of China.
authors.forename: Liuxin
authors.initials: L
authors.lastname: Xu
mesh_terms: D002384:Catalysis; D002712:Chlorides / Q000737:chemistry*; D005419:Flavonoids / Q000737:chemistry*; D017022:Flow Injection Analysis; D017612:Gold Compounds / Q000737:chemistry*; D049449:Luminescence; D008165:Luminol / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet
chemical_list: D002712:Chlorides; D005419:Flavonoids; D017612:Gold Compounds; D008165:Luminol; C024568:gold tetrachloride, acid
keywords: chemiluminescence; flavonoids; gold nanoparticles; off-line; on-line