title: A graphene oxide based fluorescence resonance energy transfer (FRET) biosensor for ultrasensitive detection of botulinum neurotoxin A (BoNT/A) enzymatic activity.
abstract: Botulinum neurotoxins (BoNTs) are among the most potent toxic bacterial proteins for humans, which make them potential agents for bioterrorism. Therefore, an ultrasensitive detection of BoNTs and their active states is in great need as field-deployable systems for anti-terrorism applications. We report the construction of a novel graphene oxide (GO)-peptide based fluorescence resonance energy transfer (FRET) biosensor for ultrasensitive detection of the BoNT serotype A light chain (BoNT-LcA) protease activity. A green fluorescence protein (GFP) modified SNAP-25 peptide substrate (SNAP-25-GFP) was optimally designed and synthesized with the centralized recognition/cleavage sites. This FRET platform was constructed by covalent immobilization of peptide substrate on GO with BSA passivation which have advantages of low non-specific adsorption and high stability in protein abundant solution. BoNT-LcA can specifically cleave SNAP-25-GFP substrate covalently immobilized on GO to release the fragment with GFP. Based on fluorescence signal recovery measurement, the target BoNT-LcA was detected sensitively and selectively with the linear detection range from 1fg/mL to 1pg/mL. The limit of detection (LOD) for BoNT-LcA is around 1fg/mL.
authors.affiliation: Interdisciplinary Division of Biomedical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, PR China.
authors.forename: Jingyu
authors.initials: J
authors.lastname: Shi
authors.affiliation: Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong, PR China.
authors.forename: Jiubiao
authors.initials: J
authors.lastname: Guo
authors.affiliation: Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, PR China.
authors.forename: Gongxun
authors.initials: G
authors.lastname: Bai
authors.affiliation: Interdisciplinary Division of Biomedical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, PR China.
authors.forename: Chunyu
authors.initials: C
authors.lastname: Chan
authors.affiliation: Institute of Textiles & Clothing, The Hong Kong Polytechnic University, Hong Kong, PR China.
authors.forename: Xuan
authors.initials: X
authors.lastname: Liu
authors.affiliation: Interdisciplinary Division of Biomedical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, PR China.
authors.forename: Weiwei
authors.initials: W
authors.lastname: Ye
authors.affiliation: Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, PR China.
authors.forename: Jianhua
authors.initials: J
authors.lastname: Hao
authors.affiliation: Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong, PR China.
authors.forename: Sheng
authors.initials: S
authors.lastname: Chen
authors.affiliation: Interdisciplinary Division of Biomedical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, PR China. Electronic address: Mo.Yang@polyu.edu.hk.
authors.forename: Mo
authors.initials: M
authors.lastname: Yang
mesh_terms: D015374:Biosensing Techniques / Q000379:methods; D019274:Botulinum Toxins, Type A / Q000032:analysis* / Q000378:metabolism; D001906:Botulism / Q000382:microbiology; D003014:Clostridium botulinum / Q000201:enzymology*; D057075:Enzyme Assays / Q000379:methods; D031541:Fluorescence Resonance Energy Transfer / Q000379:methods*; D006108:Graphite / Q000737:chemistry*; D049452:Green Fluorescent Proteins / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D055767:Immobilized Proteins / Q000737:chemistry / Q000378:metabolism; D057230:Limit of Detection; D010087:Oxides / Q000737:chemistry; D010455:Peptides / Q000737:chemistry* / Q000378:metabolism
chemical_list: D055767:Immobilized Proteins; D010087:Oxides; D010455:Peptides; D049452:Green Fluorescent Proteins; D006108:Graphite; D019274:Botulinum Toxins, Type A
keywords: Botulinum neurotoxins (BoNTs); Graphene oxide (GO); Green fluorescence protein (GFP); Optical detection; SNAP-25