title: Electrochemiluminescent Sensing for Caspase-3 Activity Based on Ru(bpy)3(2+)-Doped Silica Nanoprobe.
abstract: Caspase-3 is one of the most frequently activated cysteine proteases during the apoptosis process and has been identified as a well-established cellular marker of apoptosis. In this study, a novel approach for the sensitive determination of caspase-3 activity was proposed using electrochemiluminescence (ECL) of Ru(bpy)3(2+)-doped silica (Ru@SiO2) with tripropylamine (TPA) as coreactant. A nanocomposite containing gold nanoparticles (AuNPs), poly(dimethyldiallyl ammonium chloride) (PDDA), and multiwalled carbon nanotubes (CNTs) was fabricated as an ECL platform. The biotinylated DEVD-peptide (biotin-Gly-Asp-Gly-Asp-Glu-Val-Asp-Gly-Cys) was immobilized on the nanocomposite surface via the strong bonding interaction between AuNPs and the thiol group. Then the streptavidin-modified Ru(bpy)3(2+)-doped silica (Ru@SiO2-SA) was immobilized on the ECL platform via the specific interaction between biotin and streptavidin to generate ECL signal. Caspase-3 can specifically recognize and cleave the N-terminus of DEVD, leading to the loss of the biotin label and the decrease of ECL intensity to determine the activity of caspase-3. The results revealed a new ECL avenue for the sensitive and specific monitor of caspase-3, and the platform could be utilized to evaluate anticancer drugs.
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University , Nanjing 210093, China.|School of Chemistry and Chemical Engineering, Anhui University of Technology , Maanshan 243002, China.
authors.forename: Yong-Ping
authors.initials: YP
authors.lastname: Dong
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University , Nanjing 210093, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University , Nanjing 210093, China.|School of Chemistry and Chemical Engineering, Anhui University of Technology , Maanshan 243002, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University , Nanjing 210093, China.
authors.forename: Jun-Jie
authors.initials: JJ
authors.lastname: Zhu
mesh_terms: D015082:2,2'-Dipyridyl / Q000031:analogs & derivatives* / Q000737:chemistry; D053148:Caspase 3 / Q000032:analysis* / Q000378:metabolism; D056831:Coordination Complexes; D055664:Electrochemical Techniques; D004789:Enzyme Activation; D006046:Gold / Q000737:chemistry; D006801:Humans; D020014:K562 Cells; D049449:Luminescence; D053768:Metal Nanoparticles / Q000737:chemistry; D049329:Nanostructures / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry*; D014407:Tumor Cells, Cultured; D017975:Ruthenium Compounds
chemical_list: D015082:2,2'-Dipyridyl; D053148:Caspase 3; D056831:Coordination Complexes; D006046:Gold; D037742:Nanotubes, Carbon; D012822:Silicon Dioxide; C547232:tris(2,2-bipyridine)-ruthenium(II); D017975:Ruthenium Compounds