title: Fabrication of peptide stabilized fluorescent gold nanocluster/graphene oxide nanocomplex and its application in turn-on detection of metalloproteinase-9.
abstract: This study introduces the double-ligands stabilizing gold nanoclusters and the fabrication of gold nanocluster/graphene nanocomplex as a "turn-on" fluorescent probe for the detection of cancer-related enzyme matrix metalloproteinase-9. A facile, one-step approach was developed for the synthesis of fluorescent gold nanoclusters using peptides and mercaptoundecanoic acid as co-templating ligands. The peptide was designed to possess a metalloproteinase-9 cleavage site and to act not only as a stabilizer but also as a targeting ligand for the enzyme detection. The prepared gold nanoclusters show an intense red fluorescence with a broad adsorption spectrum. In the presence of the enzyme, due to the excellent quenching properties and the negligible background of graphene oxide, the developed peptide-gold nanocluster/graphene nanocomplex yielded an intense "turn-on" fluorescent response, which strongly correlated with the enzyme concentration. The limit of detection of the nanocomplex was 0.15nM. The sensor was successfully applied for "turn-on" detection of metalloproteinase-9 secreted from human breast adenocarcinoma MCF-7 cells with high sensitivity, selectivity, significant improvement in terms of detection time and simplicity.
authors.affiliation: School of Integrative Engineering, Chung-Ang University, Heukseok-dong, Dongjak-gu, Seoul 156-756, Republic of Korea.
authors.forename: Phuong-Diem
authors.initials: PD
authors.lastname: Nguyen
authors.affiliation: School of Integrative Engineering, Chung-Ang University, Heukseok-dong, Dongjak-gu, Seoul 156-756, Republic of Korea.
authors.forename: Vu Thanh
authors.initials: VT
authors.lastname: Cong
authors.affiliation: School of Integrative Engineering, Chung-Ang University, Heukseok-dong, Dongjak-gu, Seoul 156-756, Republic of Korea.
authors.forename: Changyoon
authors.initials: C
authors.lastname: Baek
authors.affiliation: School of Integrative Engineering, Chung-Ang University, Heukseok-dong, Dongjak-gu, Seoul 156-756, Republic of Korea. Electronic address: junmin@cau.ac.kr.
authors.forename: Junhong
authors.initials: J
authors.lastname: Min
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D005456:Fluorescent Dyes / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D008024:Ligands; D057230:Limit of Detection; D061986:MCF-7 Cells; D020780:Matrix Metalloproteinase 9 / Q000032:analysis*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D010087:Oxides / Q000737:chemistry; D010455:Peptides / Q000737:chemistry; D013050:Spectrometry, Fluorescence / Q000379:methods
chemical_list: D005456:Fluorescent Dyes; D008024:Ligands; D010087:Oxides; D010455:Peptides; D006046:Gold; D006108:Graphite; D020780:Matrix Metalloproteinase 9
keywords: Cancer metastasis; Cleavage site; Fluorescent quenching; Gold nanocluster; Graphene oxide; Metalloproteinase-9; Peptide