Nanoprobes

Dai H, Hafner J H, Rinzier A G, Colbert D T and Smalley R E 1996 Nanotubes as nanoprobes in soanning probe miorosoopy Nature 384 147... 

One of the new trends in chemical analysis appeared in the last decade is that the miniaturization. It becomes apparent in the miniaturization of analytical devices, separation procedures, measuring tools, analyzing samples and as a consequent the term micro have appeared. Further development of this trend have led to transfer from the term micro to nano one (nanoparticles, nanofluides, nanoprobes, nanoelectrodes, nanotubes, nanoscale, nanobarcode, nanoelectrospray, nanoreactors, etc). Thereupon a nanoscale films produced by Langmuir-Blodgett (LB) technique are proposed for modifying of chemical sensors. 

The wide use of microhardness testing recently prompted Oliver (1993) to design a mechanical properties microprobe ( nanoprobe would have been a better name), which generates indentations considerably less than a micrometre in depth. Loads up to 120 mN (one mN 0.1 g weight) can be applied, but a tenth of that amount is commonly used and hardness is estimated by electronically measuring the depth of impression while the indentor is still in contact. This allows, inter alia, measurement... 

Fig. 42 —AES surface survey of elements in the disk substrate surface after polishing. The slurry contains 6 wt % Si02 particles with a diameter of 30 nm, 1 wt % oxidizer and 2 wt % lubricant in Dl water, and pH value of the slurry is 1.8. (a) Elements in the disk surface, (b) deep distribution of the elements. (The contents of elements and their deep distribution in the polished surface were analyzed by using a PHI 680 auger nanoprobe under determining conditions as follows ion beam current of 1 u,A, ion beam voltage of 2 kV, electron beam current of 10 nA, electron beam voltage of 10 kV and scan area of 20 fj.m by 20...

The cellular reaction product consisted of alternating plates of C03W lamellae in a solute-depleted Co matrix (eCo). Ffomogenized ingots were cut into slices 1 mm thick and then heat-treated. Spark erosion was used to trepan 3 mm diameter discs which were then jet electropolished to form thin foils for TEM examination in a Philips EM 430 STEM instrument operating at 300 kV in the nanoprobe mode with a probe size of 5 to 10 nm. 

The Physical Electronics 680 Nanoprobe employs a field emission electron gun, and this results in a spatial resolution of less than lOnm. Ion bombardment for depth profiling is available in the SAM, and both the electron beam and the ion beam are computer controlled so that depth profiles can be run automatically, and maps and line scan of Auger electron distributions can be generated. 

Only in a few cases are test samples measurable without any treatment. As a rule, test samples have to be transformed into a measurable form that optimally corresponds to the demands of the measuring technique. Therefore, sample preparation is a procedure that converts a test sample into a measuring sample. Whereas test samples represent the material in its original form, measuring samples embodies a form that is able to interact with the measuring system in an optimum way. In this sense, measuring samples can be solutions, extracts, pellets, and melt-down samples, but also definite surface layers and volumes in case of micro- and nanoprobe techniques. 

The following sections discuss the preparation of colloidal gold suspensions of various particle sizes and their use in labeling proteins for detection purposes. Gold-labeled molecules and proteins are available from a number of manufacturers (Janssen, E-Y Labs, and Nanoprobes). 

Designing nanoprobes whereby imaging agents (for PET, SPECT, and/or optical imaging methods, as well as for simultaneous imaging and therapy) are anchored to (or encapsulated by) nanosize carriers is a topical issue (144). 

A. G. Zacarias, M. Castro, J. M. Tour, J. M. Seminario, Lowest Energy States of Small Pd Clusters Using Density Functional Theory and Standard ab Initio Methods. A Route to Understanding Metallic Nanoprobes, J. Rhys. Chem. A. 1999,103,7692-7700. 

Ameba resin was characterized by the diagnostic aldehyde signal at 10.5 ppm using Nanoprobe JH NMR.4 Checkers characterized Ameba resin by the diagnostic aldehyde signals at 1675-1684 cm 1 using IR. 

Anker JN, Kopelman R (2003) Magnetically modulated optical nanoprobes. Appl Phys Lett 82 1102-1104... 

To overcome the problem of sample availability, smaller volume NMR probes, nanoprobes , have been introduced for structure elucidations of samples that were previously considered too small for NMR analysis. 43 ... 

Optical nanoprobes are preferably designed as core/shell nanostructures where the optically active material is located in the core. A general schematic of such a nanoparticle is indicated in Fig. 1 and the typical synthesis steps are as follows ... 

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