title: Paper-based biosensor relying on flower-like reduced graphene guided enzymatically deposition of polyaniline for Pb(2+) detection.
abstract: A multi-amplified paper-based electrochemical strategy using Pb(2+) dependent DNAzyme as the recognition unit for Pb(2+) detection was developed. In this work, flower-like reduced graphene (FrGO) was prepared utilizing flower-like ZnO as template, which was first one step grown on the gold nanoparticles modified paper working electrode (Au-PWE). After being treated with acid and then modified with Au, a novel sensor platform named Au/FrGO/Au-PWE with large specific surface area and good electrical conductivity was fabricated. The Mn2O3 nanoparticle-assembled hierarchical hollow spheres (H-Mn2O3) was served as nanocarrier to immobilize GOx, HRP and signal strand (S3), resulting to the formation of S3/H-Mn2O3/HRP/GOx bioconjugations. In the presence of Pb(2+), the DNAzyme (S1) was activated and the substrate strand (S2) was cleaved. After the incubation with S3/H-Mn2O3/HRP/GOx in 0.1M HAc-NaAc solution (pH 4.3) containing 30 mM aniline and 15 mM glucose, a readily measurable "turn-on" electrochemical signal could be measured. On the basis of the signal amplification strategy of Au/FrGO/Au-PWE sensing platform and S3/H-Mn2O3/HRP/GOx bioconjugations, the developed biosensor exhibited a good linear response toward over a wide range of concentration from 0.005 to 2000 nM.
authors: School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China; Shandong Provincial Key Laboratory of Preparation and Measurement of Building Materials, University of Jinan, Jinan 250022, PR China.
authors: Shenguang
authors: S
authors: Ge
authors: School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China.
authors: Kaiqing
authors: K
authors: Wu
authors: School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China.
authors: Yan
authors: Y
authors: Zhang
authors: School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China.
authors: Mei
authors: M
authors: Yan
authors: School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, PR China. Electronic address: ujn.yujh@gmail.com.
authors: Jinghua
authors: J
authors: Yu
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry*; D015374:Biosensing Techniques; D021881:DNA, Catalytic / Q000737:chemistry; D055664:Electrochemical Techniques; D054856:G-Quadruplexes; D006046:Gold / Q000737:chemistry; D006108:Graphite / Q000737:chemistry; D006427:Hemin / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000737:chemistry; D007854:Lead / Q000737:chemistry / Q000302:isolation & purification*; D053768:Metal Nanoparticles / Q000737:chemistry; D010209:Paper
chemical_list: D000814:Aniline Compounds; D021881:DNA, Catalytic; C416807:polyaniline; D007854:Lead; D006427:Hemin; D006046:Gold; D006108:Graphite; D006861:Hydrogen Peroxide
keywords: DNAzyme; Flower-like reduced graphene; Paper; Pb(2+)