SPIFAN Nutrients ERP Book_9-29-15

FOS-04 FOR ERP USE ONLY DO NOT DISTRIBUTE

equilibrated with 50 mM NaOH for 15 minutes (see Figure 2-1 below). Column and detector compartment are maintained at 20 ° C. 2. Injection – A single 4 µL injection of each sample test solution is made. At the start of each sequence, 6 precision injections are made to ensure that system is stable, followed by the 4 levels of working standard. Samples are bracketed with working standards after every 13 injections. Autosampler is maintained at 10 ° C. 3. Electrochemical detector parameters – This method utilizes the carbohydrate triple waveform referred to in Thermo/Dionex Tech Note 21, Waveform B (4). Note this waveform is not appropriate for disposable gold electrodes! The reference electrode is set to AgCl mode. 4. Retention times – Typically fructose elutes around 10-11 minutes and glucoheptose around 16-18 minutes (see figure 2-2 below).

Figure 2-1 Quantitative Fructan Determination Gradient

Figure 2-2 Working standard chromatogram

Calculations 1.

Fructose Stock Standard – Concentration is calculated as follows:

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