TY - CHAP A1 - Koch, Claudia A1 - Poghossian, Arshak A1 - Wege, Christina A1 - Schöning, Michael Josef ED - Wege, Christina T1 - TMV-Based Adapter Templates for Enhanced Enzyme Loading in Biosensor Applications T2 - Virus-Derived Nanoparticles for Advanced Technologies N2 - Nanotubular tobacco mosaic virus (TMV) particles and RNA-free lower-order coat protein (CP) aggregates have been employed as enzyme carriers in different diagnostic layouts and compared for their influence on biosensor performance. In the following, we describe a label-free electrochemical biosensor for improved glucose detection by use of TMV adapters and the enzyme glucose oxidase (GOD). A specific and efficient immobilization of streptavidin-conjugated GOD ([SA]-GOD) complexes on biotinylated TMV nanotubes or CP aggregates was achieved via bioaffinity binding. Glucose sensors with adsorptively immobilized [SA]-GOD, and with [SA]-GOD cross-linked with glutardialdehyde, respectively, were tested in parallel on the same sensor chip. Comparison of these sensors revealed that TMV adapters enhanced the amperometric glucose detection remarkably, conveying highest sensitivity, an extended linear detection range and fastest response times. These results underline a great potential of an integration of virus/biomolecule hybrids with electronic transducers for applications in biosensorics and biochips. Here, we describe the fabrication and use of amperometric sensor chips combining an array of circular Pt electrodes, their loading with GOD-modified TMV nanotubes (and other GOD immobilization methods), and the subsequent investigations of the sensor performance. KW - Tobacco mosaic virus (TMV) KW - Coat protein KW - Enzyme nanocarrier KW - Glucose biosensor KW - Glucose oxidase Y1 - 2018 SN - 978-1-4939-7808-3 U6 - http://dx.doi.org/10.1007/978-1-4939-7808-3 N1 - Methods in Molecular Biology, vol 1776 SP - 553 EP - 568 PB - Humana Press CY - New York, NY ER - TY - JOUR A1 - Koch, Claudia A1 - Poghossian, Arshak A1 - Schöning, Michael Josef A1 - Wege, Christian T1 - Penicillin Detection by Tobacco Mosaic Virus-Assisted Colorimetric Biosensors JF - Nanotheranostics N2 - The presentation of enzymes on viral scaffolds has beneficial effects such as an increased enzyme loading and a prolonged reusability in comparison to conventional immobilization platforms. Here, we used modified tobacco mosaic virus (TMV) nanorods as enzyme carriers in penicillin G detection for the first time. Penicillinase enzymes were conjugated with streptavidin and coupled to TMV rods by use of a bifunctional biotin-linker. Penicillinase-decorated TMV particles were characterized extensively in halochromic dye-based biosensing. Acidometric analyte detection was performed with bromcresol purple as pH indicator and spectrophotometry. The TMV-assisted sensors exhibited increased enzyme loading and strongly improved reusability, and higher analysis rates compared to layouts without viral adapters. They extended the half-life of the sensors from 4 - 6 days to 5 weeks and thus allowed an at least 8-fold longer use of the sensors. Using a commercial budget-priced penicillinase preparation, a detection limit of 100 µM penicillin was obtained. Initial experiments also indicate that the system may be transferred to label-free detection layouts. Y1 - 2018 U6 - http://dx.doi.org/10.7150/ntno.22114 SN - 2206-7418 VL - 2 IS - 2 SP - 184 EP - 196 PB - Ivyspring CY - Sydney ER - TY - JOUR A1 - Poghossian, Arshak A1 - Jablonski, Melanie A1 - Koch, Claudia A1 - Bronder, Thomas A1 - Rolka, David A1 - Wege, Christina A1 - Schöning, Michael Josef T1 - Field-effect biosensor using virus particles as scaffolds for enzyme immobilization JF - Biosensors and Bioelectronics N2 - A field-effect biosensor employing tobacco mosaic virus (TMV) particles as scaffolds for enzyme immobilization is presented. Nanotubular TMV scaffolds allow a dense immobilization of precisely positioned enzymes with retained activity. To demonstrate feasibility of this new strategy, a penicillin sensor has been developed by coupling a penicillinase with virus particles as a model system. The developed field-effect penicillin biosensor consists of an Al-p-Si-SiO₂-Ta₂O₅-TMV structure and has been electrochemically characterized in buffer solutions containing different concentrations of penicillin G. In addition, the morphology of the biosensor surface with virus particles was characterized by scanning electron microscopy and atomic force microscopy methods. The sensors possessed a high penicillin sensitivity of ~ 92 mV/dec in a nearly-linear range from 0.1 mM to 10 mM, and a low detection limit of about 50 µM. The long-term stability of the penicillin biosensor was periodically tested over a time period of about one year without any significant loss of sensitivity. The biosensor has also been successfully applied for penicillin detection in bovine milk samples. Y1 - 2018 U6 - http://dx.doi.org/10.1016/j.bios.2018.03.036 SN - 0956-5663 VL - 110 SP - 168 EP - 174 PB - Elsevier CY - Amsterdam ER -