title: Polyaniline-graphene based α-amylase biosensor with a linear dynamic range in excess of 6 orders of magnitude.
abstract: α-amylase is an established marker for diagnosis of pancreatic and salivary disease, and recent research has seen a substantial expansion of its use in therapeutic and diagnostic applications for infection, cancer and wound healing. The lack of bedside monitoring devices for α-amylase detection has hitherto restricted the clinical progress of such applications. We have developed a highly sensitive α-amylase immunosensor platform, produced via in situ electropolymerization of aniline onto a screen-printed graphene support (SPE). Covalently binding an α-amylase specific antibody to a polyaniline (PANI) layer and controlling device assembly using electrochemical impedance spectroscopy (EIS), we have achieved a highly linear response against α-amylase concentration. Each stage of the assembly was characterized using a suite of high-resolution topographical, chemical and mechanical techniques. Quantitative, highly sensitive detection was demonstrated using an artificially spiked human blood plasma samples. The device has a remarkably wide limit of quantification (0.025-1000IU/L) compared to α-amylase assays in current clinical use. With potential for simple scale up to volume manufacturing though standard semiconductor production techniques and subsequently clinical application, this biosensor will enable clinical benefit through early disease detection, and better informed administration of correct therapeutic dose of drugs used to treat α-amylase related diseases.
authors.affiliation: College of Engineering, Swansea University, Bay Campus, Swansea SA1 8QQ, UK; Centre for NanoHealth, Swansea University, Singleton Park, Swansea SA2 8PP, UK. Electronic address: r.rodriguesteixeira@swansea.ac.uk.
authors.forename: Sofia Rodrigues
authors.initials: SR
authors.lastname: Teixeira
authors.affiliation: College of Engineering, Swansea University, Bay Campus, Swansea SA1 8QQ, UK; Swansea University Medical School, Singleton Park, Swansea SA2 8PP, UK; Centre for NanoHealth, Swansea University, Singleton Park, Swansea SA2 8PP, UK.
authors.forename: Catherine
authors.initials: C
authors.lastname: Lloyd
authors.affiliation: Swansea University Medical School, Singleton Park, Swansea SA2 8PP, UK; Centre for NanoHealth, Swansea University, Singleton Park, Swansea SA2 8PP, UK.
authors.forename: Seydou
authors.initials: S
authors.lastname: Yao
authors.affiliation: Swansea University Medical School, Singleton Park, Swansea SA2 8PP, UK; Centre for NanoHealth, Swansea University, Singleton Park, Swansea SA2 8PP, UK.
authors.lastname: Andrea Salvatore Gazze
authors.affiliation: Swansea University Medical School, Singleton Park, Swansea SA2 8PP, UK; The Welsh Centre for Burns and Plastic Surgery, Morriston Hospital, Swansea SA66NL, UK.
authors.forename: Iain S
authors.initials: IS
authors.lastname: Whitaker
authors.affiliation: Swansea University Medical School, Singleton Park, Swansea SA2 8PP, UK; Centre for NanoHealth, Swansea University, Singleton Park, Swansea SA2 8PP, UK.
authors.forename: Lewis
authors.initials: L
authors.lastname: Francis
authors.affiliation: Swansea University Medical School, Singleton Park, Swansea SA2 8PP, UK; Centre for NanoHealth, Swansea University, Singleton Park, Swansea SA2 8PP, UK.
authors.forename: R Steven
authors.initials: RS
authors.lastname: Conlan
authors.affiliation: Swansea University Medical School, Singleton Park, Swansea SA2 8PP, UK; The Welsh Centre for Burns and Plastic Surgery, Morriston Hospital, Swansea SA66NL, UK.
authors.forename: Ernest
authors.initials: E
authors.lastname: Azzopardi
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry*; D000818:Animals; D055910:Antibodies, Immobilized / Q000737:chemistry*; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D055664:Electrochemical Techniques / Q000295:instrumentation / Q000379:methods; D004566:Electrodes; D004867:Equipment Design; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D007118:Immunoassay / Q000295:instrumentation / Q000379:methods; D057230:Limit of Detection; D051379:Mice; D000516:alpha-Amylases / Q000032:analysis / Q000097:blood*
chemical_list: D000814:Aniline Compounds; D055910:Antibodies, Immobilized; C416807:polyaniline; D006108:Graphite; D000516:alpha-Amylases
keywords: Antibody; Graphene; Immunosensor; Polyaniline; Screen-printed electrode; α-amylase