Double-sampling strategy

As DNA extracted from the sample, with or without PCR amplification step, usually is a double-strand, the hybridisation of the target strand with the capture probe immobilised on genosensor device cannot occur. Then, it is necessary to obtain ssDNA targets previously to test with genosensor device. Several strategies are followed to achieve ssDNA targets. 

The interpolation processor has a double buffered memory that permits updates during processing. Note that interpolation happens on every sample, thereby avoiding zipper noise due to coefficient quantization. This is an expensive strategy, however it always works. 

The acidity of precipitation is commonly presented as pH. However, it is important to also examine all of the other ions in a sample to understand the effects on the environment. There has been a suggestion put forth to limit the sulfate deposition without regard to the precipitation acidity. It is presumed that a sulfate reduction will automatically result in higher pH values, and, thus, a double environment benefit will result. But without better quantification of all sources of sulfate and their relation to acidity, any reduction strategy may not bring about the desired result. 

Loop-based injection is used for sample insertion and a similar procedure is used for displacing the tubular detector D between monitoring sites a and b (Figs 7.9 and 7.10, lower). Consequently, this strategy has usually been accomplished using two loop-based injectors or a double injection valve/commutator [81], where a flow cell with two small transmission lines replaces one of the sampling loops. Although the flow system can be manually operated, computer-controlled valves or commutators have been preferred. 

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