One-step dilution

In the example above, the sample preparation contributed 75% of the error. When multiple steps such as those shown in Figure 1.2 are involved, the uncertainty is compounded. A simple dilution example presented in Figure 1.5 illustrates this point. A 1000-fold dilution can be performed in one step 1 mL to 1000 mL. It can also be performed in three steps of 1 10 dilutions each. In the one-step dilution, the uncertainty is from the uncertainty in the volume of the pipette and the flask. In the three-step dilution, three pipettes and three flasks are involved, so the volumetric uncertainty is compounded that many times. A rigorous analysis showed [3] that the uncertainty in the one-step dilution was half of what was expected in the three-step process. 

Figure 1. Glucose yield from glucan ) and mannose yield from mannan ( in a one-step dilute-acid hydrolysis of (25% dry weight) spruce as a junction of hydrolysis temperature (1).

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