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The enhancement of a single strain DNA probe linked to the sensor surface is of crucial importance in DNA molecule recognition. By means of nanogold modification of the sensor surface in addition to the nanogold amplifier, DNA detection sensitivity higher than 10−16 mol/L was obtained in a Quartz Crystal microbalance (QCM) system, much higher than the ordinary QCM sensor without surface modification by nanogold. [Copyright &y& Elsevier]

Describes the surface modification of nanogold particles in DNA detection with quartz crystal microbalance. Effect of the gold particle size on the amount of immobilization of the probe on the surface and the hybridization rate of the target DNA; Optimal size for the surface modification.

A novel method using an amplifier with a cantilever and gold nanoparticles successfully to extend the length of the target for the specific and high sensitive detection of DNA was reported. When the size of gold nanoparticle is 50 nm, a sensitivity of 10−15 M for the single base mutation detection has been achieved. [Copyright &y& Elsevier]

A novel amplified microgravimetric gene sensing system was developed using quartz crystal microbalance modified by gold nanoparticles anchored on its 1,6-hexanedithiol modified gold electrode surface, and ultrasensitive detection of DNA hybridization was accomplished at the level of at least 2×10−16 M. [Copyright &y& Elsevier]

Abstract: In the present work, we have obtained organized PEI/PM (poly(ethylenimine)/purple membrane) multilayer films by layer-by-layer alternate adsorptions with positively charged polycation PEI and negatively charged purple membrane fragments. The results observed by UV–vis spectroscopy show that each transfer amount of PM fragments onto the substrate is equal and the characteristic absorption bands of bacteriorhodopsin (bR) are still preserved. AFM and SEM analysis investigated the morphology and cross-section of PM films, respectively. The photocurrent peaks of (PEI/PM)6 multilayer films corresponding to light-on and light-off are ca. 440 and 250nA/cm2. [Copyright &y& Elsevier]

Abstract: We have observed the morphology of an anionic polyelectrolyte (partially hydrolyzed polyacrylamide) (HPAM) adsorbed to mica surface in different environment using atomic force microscopy with molecular resolution. HPAM molecules deposited on the mica surface from aqueous solution at natural pH were observed to form a nanostructured network. However, the nanostructured network-to-globule conformational transition on mica can be directly visualized when the mica substrate with the predeposited HAPM molecules was immersed into chloroform. Meanwhile, necklace-like globule conformation on mica can be obtained in the presence of NaCl. [Copyright &y& Elsevier]

Polymer solutions have very important applications in the enhanced oil recovery due to their unique viscoelastic properties increasing microscale displacement efficiency. In this paper, the viscoelastic properties of partially hydrolyzed polyacrylamide (HPAM) solution have been investigated. Results show that the viscoelastic properties of HPAM increase with HPAM concentration increasing, and decrease with the increase of sodium dodccyl sulfate (SDS). Meanwhile, adding NaCl can destroy the viscoelastic properties. [ABSTRACT FROM AUTHOR]

Presents an experimental study of oil-water interface layers dilation rheological properties. Use of the liquid-liquid interface film pressure measurement apparatus based on the principles of Langmuir film balance; Possibility to form the interface-associated material caused by the attraction of dispersion forces at the pure alkane-water interface; Decrease in the stability of the interface-associated materials.

Presents information on a study which examined the immobilization and hybridization of DNA probes on a biosensor using gold nanoparticles. Methodology; Results and discussion; Conclusion.

Deals with a study which examined a method that can measure interface dilatation elastic module and dilatation viscosity of all surfactants based on the surface pressure relaxation process. Information on dilatation elastic module and viscosity; Theoretical basis of the method; Methodology and results; Discussion and conclusion.

Thin films of poly(allylamine hydrochloride) (PAH) and bacteriorhodopsin (bR) embedded in purple membrane (PM) have been prepared by layer-by-layer (LBL) self-assembly technique. The results obtained by UV–Vis spectroscopy and atomic force microscopy (AFM) analysis showed that the biological activity of bR was preserved and PM fragments could be well oriented onto the ITO substrate. A photo-electrochemical cell with the structure of ITO/(PAH/PM)n/electrolyte (0.5 M KCl)/Pt was fabricated and studied. The photocurrent peaks of (PAH/PM)6 corresponding to light-on and light-off were about 200 and 100 nA/cm2, respectively, with the former enhanced 30% higher than that of the reference films made of (PDAC/PM)6. [Copyright &y& Elsevier]