A novel biosensing interfacial design strategy has, for the first time, been produced by assembling nano-Au particles on amine-terminated plasma-polymerized films (PPF). A quartz-crystal microbalance (QCM) as a model transducer was deposited with PPF of n-butylamine by use of a glow discharge and then treated with nano-Au particles. The kinetic assembly process and conditions were studied using the real-time-output device and the surface topology of the resulting crystal was characterized by atomic force microscopy (AFM) imaging. Based on analysis of the experimental data, including the association constant of Au-amine interaction, the assembly mechanism is considered to be partly or even mainly chemical adsorption. Moreover, immobilization of anti-human IgM antibody (IgM Ab), as an example, on the developed PPF-Au interface was investigated. It was found that antibody molecules immobilized by the proposed procedure had higher immunological activity than those immobilized by the conventional glutaraldehyde (GLU) cross-linking procedure or the direct gold-attachment procedure. The newly developed sensor had a better response, with a detection limit of IgM concentration as low as approximately 1.00 microg mL(-1). In particular, the extremely high stability of both PPF and nano-Au monolayer formulated allows the designed biosensing interface to withstand harsh regeneration treatment, making it reusable.

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A lamellar PbSO 4 mesophase with well-crystallized walls was synthesized using sodium dodecyl sulfate (SDS) as a template and bis [3-(triethoxysilyl)propyl]tetrasulfide (TESPTS) as a structure-stabilizing agent through hydrothermal treatment method. The obtained layered mesostructure was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and high-resolution TEM (HRTEM), energy-dispersive X-ray spectroscopy (EDS), and IR spectrum. The photoluminescence properties of the products were also investigated. The sample gives two UV emission bands centered at 340 and 360 nm and four visible light emission bands in the range of 400-500 nm using an excitation wavelength of 270 nm. The results have demonstrated that TESPTS with more hydrophobic character could be responsible for the formation of this stabilized lamellar PbSO 4 mesophase. A possible formation mechanism for the lamellar PbSO 4 mesostructure was also proposed. Such lamellar mesostructures could provide a useful precursor for potential applications of PbSO 4 .