title: The development of an electrochemical immunosensor using a thiol aromatic aldehyde and PAMAM-functionalized Fe3O4@Au nanoparticles.
abstract: In this work, a novel thiol aromatic aldehyde was synthesized. It can be used as a substrate to directly immobilize antibodies on a gold electrode, for which no additional chemical cross-linker is required. It was also applied as a linker to prepare Fe3O4@Au/PAMAM/Ab2-horseradish peroxidase bioconjugates, which introduced multiple enzymes onto a sensing interface owing to the high surface-to-volume ratio of Fe3O4@Au nanoparticles and many functional groups of the poly(amidoamine) dendrimer (PAMAM). The introduced multiple enzymes greatly improved the detection signal. Under optimal conditions, the proposed electrochemical immunosensor exhibited desirable performance for detection of IgG in the range 0.005-50 ng ml(-1) with a detection limit of 3 pg ml(-1) based on a signal-to-noise ratio of 3. It has great potential application in the area of clinical analysis.
authors.affiliation: College of Chemistry and Chemical Engineering, Hunan University of Arts and Science, Changde 415000, Hunan, China.
authors.forename: Chunxiang
authors.initials: C
authors.lastname: Zhang
authors.affiliation: College of Chemistry and Chemical Engineering, Hunan University of Arts and Science, Changde 415000, Hunan, China. Electronic address: sgyrab@163.com.
authors.forename: Guangyu
authors.initials: G
authors.lastname: Shen
authors.affiliation: College of Chemistry and Chemical Engineering, Hunan University of Arts and Science, Changde 415000, Hunan, China. Electronic address: ymshen79@163.com.
authors.forename: Youming
authors.initials: Y
authors.lastname: Shen
authors.affiliation: College of Chemistry and Chemical Engineering, Hunan University of Arts and Science, Changde 415000, Hunan, China.
authors.forename: Xiangyang
authors.initials: X
authors.lastname: Zhang
mesh_terms: D000447:Aldehydes / Q000737:chemistry; D015374:Biosensing Techniques; D003432:Cross-Linking Reagents / Q000737:chemistry; D050091:Dendrimers / Q000737:chemistry*; D055664:Electrochemical Techniques; D005290:Ferric Compounds / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D013438:Sulfhydryl Compounds / Q000737:chemistry
chemical_list: D000447:Aldehydes; D003432:Cross-Linking Reagents; D050091:Dendrimers; D005290:Ferric Compounds; C104700:PAMAM Starburst; D013438:Sulfhydryl Compounds; C001215:ferrite; D006046:Gold
keywords: Fe(3)O(4)@Au/PAMAM/Ab(2)–HRP bioconjugate; IgG; Immunosensor; Self-assembled monolayer; Thiol aromatic aldehyde