GE MOA 280i - Cold Ethanol Precipitation; Zinc Sulfate;Sodium Hydroxide Precipitation

GE Analytical Instruments ©2006 11-11 DLM 14291 Rev. A
reagents are contaminated. A blank should always be included to check for
contamination.
Cold ethanol precipitation
• Rinse all glassware and tubes with deionized water to remove any
contamination.
• Chill the required volume of ethanol to 0° C.
• Place 0.5 mL of the sample in a 1.5 mL microcentrifuge tube, add 1 mL of cold
ethanol and vortex.
• Let stand at 0° C for 30 minutes.
• Centrifuge at ~14,000 RPM for 5 minutes.
• Remove the supernatant for analysis. (Remember to account for 3-fold dilution
in the calculations).
Zinc Sulfate/Sodium Hydroxide precipitation
• Rinse all glassware and tubes with deionized water to remove any residual
nitrate.
• Add 200 µL of sample to microcentrifuge tube.
• Add 400 µL of 0.5 N NaOH and 400 µL of 10% by weight aqueous ZnSO
4
.
• Vortex for 30 seconds then let stand at room temperature for 15 minutes.
• Centrifuge at ~14,000 RPM for 5 minutes.
• Remove supernatant for analysis (remember to account for 5-fold dilution in
the calculations).