Multiprobe method

There are two molecular probe methods available for the determination of surface fractal dimension. One is the multiprobe method (MP method),83,84,87-100 which uses several kinds of multiprobe molecules with different molecular sizes and requires the number of adsorbed molecules to form a monolayer Nmoao for each probe molecule. If the probe molecule is varied through a series of spheres with radius rm, the surface fractal dimension is given by Eq. (7) ... 

F,MP Surface fractal dimension determined by the multiprobe method using gas adsorption... 

The RPA is a highly sensitive and specific method for the detection and quantitation of mRNA species. Pharmingen has developed a multiprobe RPA system to generate a series of apoptosis-related gene templates, each of distinct length and each representing a sequence in a distinct mRNA species. The templates are... 

This multiprobe RPA offers the advantages of its sensitivity and capacity to simultaneously quantitate several mRNA species in a single sample of total RNA. This allows comparative analysis of different mRNA species within samples, moreover, by incorporating probes for housekeeping gene transcripts, the levels of individual mRNA species can be compared between samples. Furthermore, the assay is highly specific and quantitative owing to the RNase sensitivity of mismatched base pairs and the use of solution-phase hybridization driven toward completion by excess probe. Finally, the multiprobe RPA can be performed on total RNA preparations derived by standard methods from either frozen tissues or cultured cells. 

The fast-gradient method, in contrast, retains analytes on-column until well after the solvent front has eluted. Overall sample throughput is increased with fast-gradient methods due to reduced analytical run time, decreased method development time, and fewer repeat analyses. Onorato et al. [90] used a multiprobe autosampler for parallel sample injection, short, small-bore columns, high flow rates, and elevated HPLC column temperatures to perform LC separations of idoxifene and its metabolite at 10 s/sample. Sample preparation employed liquid liquid extraction in the 96-well format. An average run time of 23 s/sample was achieved for human clinical plasma samples. 

Bubendorf L, Grilli B. UroVysion multiprobe PISH in urinary cytology. Methods Mol Med. 2004 97 117-131. 

At present, no calibration procedure for black and white standard thermometer is available that includes all stress factors (air temperature, air velocity, and humidity). Today, calibration traceability is guaranteed by a contact thermometric procedure. It would be preferable to measure the temperature at the surface of the coated sensor because this is the temperature of interest. A contactless surface temperature measurement requires knowing the emission ratio of the material and a minimization of the reflected and scattered radiation. For a minor error contact surface temperature measurement, a known method is the multiprobe measurement with extrapolation to the surface temperature. 

Figure 11.3 shows a diagram of a flexible and efficient dilution method that can handle a wide range of requirements. The basic approach is to use deepwell plates for intermediate dilutions. Each sample undergoes one to three intermediate dilutions depending on the total dilution factor required. Once the intermediate dilutions are performed, the sample is transferred into a final location where serial dilutions are performed (if needed). Figure 11.4 shows a Multiprobe II deck layout for this protocol. 

FIGURE 11.4 A Multiprobe II deck layout for the above dilution method. 

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