Molecular-interfaced alcohol

Molecular-interfaced alcohol dehydrogenase with NAD and its response to ethanol. It has been difficult to incorporate dehydrogenases that are coupled with NAD(P) into amperometric enzyme sensors owing to the irreversible electrochemical reaction of NAD. We have developed a molecular-interfaced alcohol dehydrogenase on the surface of an electrode on which NAD is electrochemical 1 y regenerated within a membrane matrix. 

The importance of surface characterization in molecular architecture chemistry and engineering is obvious. Solid surfaces are becoming essential building blocks for constructing molecular architectures, as demonstrated in self-assembled monolayer formation [6] and alternate layer-by-layer adsorption [7]. Surface-induced structuring of liqnids is also well-known [8,9], which has implications for micro- and nano-technologies (i.e., liqnid crystal displays and micromachines). The virtue of the force measurement has been demonstrated, for example, in our report on novel molecular architectures (alcohol clusters) at solid-liquid interfaces [10]. 

Stanners et al. [29] used VSFS to study the structure of the alcohols at the liquid I air interface. For low-molecular-mass alcohols, namely, methanol to butanol, the alcohol molecule is oriented with the hydroxy group in the liquid and the alkyl group pointing into the gas phase. This orientation is attributed to the effects of hydrogen bonding involving the hydroxy group and other alcohol molecules in the bulk. The infrared data involved both the -OH and -CH stretch-... 

The authors have successfully interfaced fructose dehydrogenase and alcohol dehydrogenase on the electrode surface with conducting polymer of polypyrrole, which could cause these enzymes to make an electron transfer with retaining their enzymatic activity. The molecular-interfaced redox enzymes will find their application in fabricating biosensors that respond specifically to the corresponding substrates in current. 

Electronic communication of fructose dehydrogenase (FDH) with a Pt electrode was accomplished through the conducting polymer molecular interface. Electrons were reversibly transferred between the active center of FDH and the electrode surface when the electrode potential was properly controlled. The enzyme activity of the molecular-interfaced FDH was found to be modulated in the presence of D-fructose by the electrode potential. Electronic communication of alcohol dehydrogenase (ADH) with a Pt electrode was also accomplished in the... 

Adsorption processes, undesirability, 280 Alcohol dehydrogenase, molecular interfacing with nicotinamide adenine dinucleotide, 311-312,313/... 

The external reflection of infrared radiation can be used to characterize the thickness and orientation of adsorbates on metal surfaces. Buontempo and Rice [153-155] have recently extended this technique to molecules at dielectric surfaces, including Langmuir monolayers at the air-water interface. Analysis of the dichroic ratio, the ratio of reflectivity parallel to the plane of incidence (p-polarization) to that perpendicular to it (.r-polarization) allows evaluation of the molecular orientation in terms of a tilt angle and rotation around the backbone [153]. An example of the p-polarized reflection spectrum for stearyl alcohol is shown in Fig. IV-13. Unfortunately, quantitative analysis of the experimental measurements of the antisymmetric CH2 stretch for heneicosanol [153,155] stearly alcohol [154] and tetracosanoic [156] monolayers is made difflcult by the scatter in the IR peak heights. 

The ion spray liquid chromatography/mass spectrometry (LC-MS) interface coupled via a postsuppressor split with an ion chromatography (IC) has been used in the analysis of alcohol sulfates. The IC-MS readily produces the molecular weight while the tandem mass spectrometric detection IC-MS-MS provides structural information [305]. 

Surface forces measurement is a unique tool for surface characterization. It can directly monitor the distance (D) dependence of surface properties, which is difficult to obtain by other techniques. One of the simplest examples is the case of the electric double-layer force. The repulsion observed between charged surfaces describes the counterion distribution in the vicinity of surfaces and is known as the electric double-layer force (repulsion). In a similar manner, we should be able to study various, more complex surface phenomena and obtain new insight into them. Indeed, based on observation by surface forces measurement and Fourier transform infrared (FTIR) spectroscopy, we have found the formation of a novel molecular architecture, an alcohol macrocluster, at the solid-liquid interface. 

Pohorille, A. Wilson, M.A. Chipot, C., Interaction of alcohols and anesthetics with the water-hexane interface a molecular dynamics study, Prog. Coll. Polym. Sci. 1997,103, 29A0... 

The formation of complexes is not restricted to mixtures of polyectrolytes and surfactants of opposite charge. Neutral polymers and ionic surfactants can also form bulk and/or surface complexes. Philip et al. [74] have studied the colloidal forces in presence of neutral polymer/ionic surfactant mixtures in the case where both species can adsorb at the interface of oil droplets dispersed in an aqueous phase. The molecules used in their studies are a neutral PVA-Vac copolymer (vinyl alcohol [88%] and vinyl acetate [12%]), with average molecular weight M = 155000 g/mol, and ionic surfactants such as SDS. The force measurements were performed using MCT. The force profiles were always roughly linear in semilogarithmic scale and were fitted by a simple exponential function ... 

Hydrazine may be derivatized with salicylaldehyde to a hydrazone derivative, separated on a suitable HPLC column and determined by a UV detector. Aqueous samples may be directly injected into a polar GC column interfaced to an FID. Anhydrous hydrazine may be appropriately diluted in alcohol or ether and determined by GC/MS. The molecular ion for GC/MS determination by electron-impact ionization is 32. 

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