title: Fluorescent artificial enzyme-linked immunoassay system based on Pd/C nanocatalyst and fluorescent chemodosimeter.
abstract: Artificial enzyme mimics have recently attracted considerable interest because they possess many advantages compared with natural enzymes, such as low cost of preparation and high stability. Herein, we present a novel fluorescent artificial enzyme-linked immunoassay strategy by utilizing Pd/C nanocatalyst as the enzyme mimic and bis-allyloxycarbonyl rhodamine 110 (BI-Rho 110) as the substrate, and the amplification procedure is based on the palladium-catalyzed Tsuji-Trost reaction. Pd/C nanocatalyst with the average size of 150 nm was prepared by the impregnation-reduction method, and high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) analyses reveal that Pd clusters with an average size of about 1 nm are dispersed uniformly on each carbon nanosphere's surface. Kinetic studies show that this reaction follows Michaelis-Menten kinetics and the fluorescence intensity is proportional to the concentration of Pd/C nanocatalyst under certain conditions. The turnover number of Pd/C nanocatalyst reaches up to 3.3 × 10(7) (h(-1)). The analytical performance of this system in detecting hCG shows that after a 24 h incubation the sensitivity limit can reach 0.1 ng/mL and the dynamic linear working range is 1-10 ng/mL. Our findings pave the way to use Pd-catalyzed reaction for design and development of novel analytical methods.
authors.affiliation: School of Chemistry and Chemical Engineering, Southeast University , Nanjing, Jiangsu 211189, China.
authors.forename: Zhifei
authors.initials: Z
authors.lastname: Wang
authors.forename: Shuang
authors.initials: S
authors.lastname: Zheng
authors.forename: Jin
authors.initials: J
authors.lastname: Cai
authors.forename: Peng
authors.initials: P
authors.lastname: Wang
authors.forename: Jie
authors.initials: J
authors.lastname: Feng
authors.forename: Xia
authors.initials: X
authors.lastname: Yang
authors.forename: Liming
authors.initials: L
authors.lastname: Zhang
authors.forename: Min
authors.initials: M
authors.lastname: Ji
authors.forename: Fugen
authors.initials: F
authors.lastname: Wu
authors.forename: Nongyue
authors.initials: N
authors.lastname: He
authors.forename: Neng
authors.initials: N
authors.lastname: Wan
mesh_terms: D000818:Animals; D002244:Carbon / Q000737:chemistry*; D002384:Catalysis; D058501:Enzyme-Linked Immunospot Assay / Q000379:methods*; D005456:Fluorescent Dyes / Q000737:chemistry*; D006801:Humans; D051379:Mice; D054118:Nanospheres / Q000737:chemistry*; D010165:Palladium / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D005456:Fluorescent Dyes; D010165:Palladium; D002244:Carbon