title: Engineered self-assembling monolayers for label free detection of influenza nucleoprotein.
abstract: Integrating nanotechnology into useable devices requires a combination of bottom up and top down methodology. Often the techniques to measure and control these different components are entirely different, so methods that can analyse the nanoscale component in situ are of increasing importance. Here we describe a strategy that employs a self-assembling monolayer of engineered protein chimeras to display an array of oriented antibodies (IgG) on a microelectronic device for the label free detection of influenza nucleoprotein. The structural and functional properties of the bio-interface were characterised by a range of physical techniques including surface plasmon resonance, quartz-crystal microbalance and neutron reflectometry. This combination of methods reveals a 13.5 nm thick engineered-monolayer that (i) self-assembles on gold surfaces, (ii) captures IgG with high affinity in a defined orientation and (iii) specifically recognises the influenza A nucleoprotein. Furthermore we also show that this non-covalent self-assembled structure can render the dissociation of bound IgG irreversible by chemical crosslinking in situ without affecting the IgG function. The methods can thus describe in detail the transition from soluble engineered molecules with nanometre dimensions to an array that demonstrates the principles of a working influenza sensor.
authors: Bragg Institute, Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW, 2232, Australia.
authors: Anton P
authors: AP
authors: Le Brun
authors: Andrei
authors: A
authors: Soliakov
authors: Deepan S H
authors: DS
authors: Shah
authors: Stephen A
authors: SA
authors: Holt
authors: Alison
authors: A
authors: McGill
authors: Jeremy H
authors: JH
authors: Lakey
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D007118:Immunoassay / Q000295:instrumentation*; D007251:Influenza, Human / Q000378:metabolism*; D055617:Micro-Electrical-Mechanical Systems / Q000295:instrumentation*; D019590:Nucleocapsid Proteins; D015202:Protein Engineering / Q000379:methods*; D016601:RNA-Binding Proteins / Q000032:analysis* / Q000737:chemistry; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013194:Staining and Labeling; D020349:Surface Plasmon Resonance / Q000295:instrumentation*; D014758:Viral Core Proteins / Q000032:analysis* / Q000737:chemistry
chemical_list: C048842:NP protein, Influenza A virus; D019590:Nucleocapsid Proteins; D016601:RNA-Binding Proteins; D014758:Viral Core Proteins