title: Bifunctional magnetic nanobeads for sensitive detection of avian influenza A (H7N9) virus based on immunomagnetic separation and enzyme-induced metallization.
abstract: Bifunctional magnetic nanobeads (bi-MBs) were fabricated by co-immobilizing target recognition molecules and signal molecules on a magnetic nanobead surface, which were used as both separation and enrichment carriers and signal carriers. The bi-MBs could capture and separate avian influenza A (H7N9) virus (H7N9 AIV) from complex samples efficiently based on the specific reaction between antigen-antibody and their good magnetic response, which simplified sample pretreatment and saved the detection time. Taking advantages of their high surface to volume ratio and rich surface functional groups, multiple alkaline phosphatase (ALP) signal molecules were tethered on the surface of bi-MBs which greatly amplified the detection signal. As an efficient signal amplification strategy, enzyme-induced metallization had been integrated with bi-MBs and anodic stripping voltammetry to construct an ultrasensitive electrochemical immunosensor for H7N9 AIV detection. Under the optimal conditions, the introduction of bi-MBs could amplify the detection signal in about four times compared with the same immunoassay without MBs, and the method showed a wide linear range of 0.01-20 ng/mL with a detection limit of 6.8 pg/mL. The electrochemical immunosensor provides a simple and reliable platform with high sensitivity and selectivity which shows great potential in early diagnosis of diseases.
authors: Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, State Key Laboratory of Virology, Wuhan University, Wuhan 430072, PR China.
authors: Zhen
authors: Z
authors: Wu
authors: Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, State Key Laboratory of Virology, Wuhan University, Wuhan 430072, PR China; Key Laboratory of Medicinal Chemistry for Natural Resource (Ministry of Education), School of Chemical Science and Technology, Yunnan University, Kunming 650091, PR China.
authors: Chuan-Hua
authors: CH
authors: Zhou
authors: CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China. Electronic address: chenjj126@126.com.
authors: Jian-Jun
authors: JJ
authors: Chen
authors: CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, PR China.
authors: Chaochao
authors: C
authors: Xiong
authors: Shanghai Institute of Biological Products, PR China.
authors: Ze
authors: Z
authors: Chen
authors: Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, State Key Laboratory of Virology, Wuhan University, Wuhan 430072, PR China.
authors: Dai-Wen
authors: DW
authors: Pang
authors: Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, State Key Laboratory of Virology, Wuhan University, Wuhan 430072, PR China. Electronic address: zlzhang@whu.edu.cn.
authors: Zhi-Ling
authors: ZL
authors: Zhang
mesh_terms: D000818:Animals; D015374:Biosensing Techniques / Q000379:methods*; D001717:Birds; D006046:Gold / Q000737:chemistry; D006801:Humans; D018189:Immunomagnetic Separation; D064766:Influenza A Virus, H7N9 Subtype / Q000302:isolation & purification* / Q000472:pathogenicity; D005585:Influenza in Birds / Q000175:diagnosis / Q000821:virology*; D007251:Influenza, Human / Q000175:diagnosis / Q000821:virology*; D060328:Magnetic Phenomena
chemical_list: D006046:Gold
keywords: Avian influenza A (H7N9) virus; Bifunctional magnetic nanobeads; Electrochemical immunosensor; Enzyme-induced metallization