RESUMO
The contribution of advanced nanoscale chemical and biological devices to life science has been limited to a small number of nanomaterials, due to the absence of effective surface modification routes. Herein, we demonstrate a polymer-like nanosheath synthesized by nonthermal plasma technology (NPT) that can protect the core nanomaterial from the solution environment and provide a multifunctional platform for chemical and biological nanosensors. For ZnO nanowires (NWs) which are unstable in solution, we demonstrate that this nanosheath makes it possible for ZnO NW field-effect transistors to act as a pH sensor for 24 h and a biosensor for the real-time, label-free detection of liver cancer markers.
Assuntos
Biomarcadores Tumorais/análise , Técnicas Biossensoriais/métodos , Carbono/química , Técnicas de Química Analítica/métodos , Neoplasias Hepáticas/diagnóstico , Nanoestruturas/química , Óxido de Zinco/química , Eletrodos , Humanos , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Propriedades de Superfície , Transistores EletrônicosRESUMO
We present a systematic study on the effect of oxygen and hydrogen plasma-generated reactive species on the properties of ZnO nanowires. Upon exposure to oxygen plasma, the electrical conductivity of an individual ZnO nanowire decreased with substantial changes in the surface chemistry, indicating a decrease in the number of donor-like defects and an increase in the number of electron-trapping species. In contrast, an individual ZnO nanowire exposed to hydrogen plasma showed a drastic increase in conductivity up to two orders of magnitude due to the incorporated hydrogen acting as a shallow donor inside the ZnO nanowires without a sputtering process.