SPSFAM ERP

(c) Mobile Phase B (100 mM sodium hydroxide).—Measure 2000 mL of water into a 2 L graduated cylinder. Transfer approximately 1900 mL to a 2 L polypropylene mobile phase container. Vacuum degas or helium sparge for approximately 5 minutes. Add 16 ± 0.1 g of 50 % (w/w) sodium hydroxide to the container, and add the remaining volume from the 2 L cylinder. Add a stir bar and stir slowly for 10 minutes. Keep under inert gas while in use on the instrument. (d) Mobile Phase C and Auxiliary Pump (200 mM sodium hydroxide).—Measure 2000 mL of water into a 2 L graduated cylinder. Transfer approximately 1900 mL to a 2 L polypropylene mobile phase container. Vacuum degas or helium sparge for approximately 5 minutes. Add 32.0 ± 0.1 g of 50 % (w/w) sodium hydroxide to the container, and add the remaining volume from the 2 L cylinder. Add a stir bar and stir slowly for 10 minutes. Keep under inert gas while in use on the instrument. (e) Mobile Phase D (600 mM sodium hydroxide).—Measure 2000 mL of water into a 2 L graduated cylinder. Transfer approximately 1900 mL to a 2 L polypropylene mobile phase container. Vacuum degas or helium sparge for approximately 5 minutes. Add 96.0 ± 0.1 g of 50 % (w/w) sodium hydroxide to the container, and add the remaining volume from the 2 L cylinder. Add a stir bar and stir slowly for 10 minutes. Keep under inert gas while in use on the instrument. (a) Internal Standard Stock Solution (100 mg/mL arabinose).—Weigh 10.00 ± 0.01 g of arabinose. Transfer to 100-mL volumetric flask. Add approximately 10 mg sodium azide to the flask (weight not recorded). Add approximately 80 mL water. Stir until completely dissolved and sonicate as needed. Bring to volume with water. (b) Intermediate Internal Standard Solution (1,000 µ g/mL arabinose).—Pipet 1 mL of Internal Standard Stock Solution into a 100-mL volumetric flask. Add approximately 10 mg sodium azide to the flask (weight not recorded). Dilute to volume with water. Mix well. (c) Reference Standard Stock Solution (~100 µ g/mL each compound).—Weigh 0.10000 ± 0.005 g of each reference standard into a single 1000-mL volumetric flask. Add approximately 0.1 g sodium azide to the flask (weight not recorded). Fill flask about ¾ full with water. Mix thoroughly until standard is dissolved. Sonicate the flask as necessary until all standards are dissolved. Allow flask to cool to room temperature and bring to volume with water. (d) Calibration Standard Working Solutions (WS1 – WS5).—Prepare the calibration standard working solutions by combining appropriate volumes of the Intermediate Internal Standard solution and the Reference Standard Stock solution in separate 200 mL volumetric flasks as indicated in the table below. Add approximately 20 mg of sodium azide to each (weight recording not required). Bring to volume with water and mix each solution well. E. Preparation of Standard Solutions