XIT™ Genomic DNA Blood Kit Protocol for Purificaton of DNA from Amniotic Fluid
Add 1‐3ml Amniotic fluid to a 1.5ml centrifuge tube .
Centrifuge 14,000xg for 5 seconds then remove supernatant carefully without disturbing the pellet .
Remove supernatant leaving 10‐20µl residual liquid in the tube .
Vortex the tube to resuspend the cells in the residual liquid .
Add 400µl of XIT™ Lysis Buffer to the resuspended cells and vortex vigorously to lyse the cells .
Usually no incubation is required ; however , if cell clumps are visible after mixing , incubate at 37°C for 5‐10 minutes or until the solution is homogenous .
Place the tube on ice for 1 minute to rapidly cool to room temperature .
Add 90µl XIT™ Protein Precipitation Buffer to the sample and mix by inverting the tube 10‐20 times .
Centrifuge at 16,000g for 5 minutes .
Carefully , transfer the supernatant to a new tube .
Add 400µl isopropanol and 5µl Glycogen Solution to the supernatant and mix by gently inverting the sample at least 20‐25 times .
Centrifuge at 14,000rpm for 5 minutes .
Discard the supernatant and use a pipette to carefully remove remaining liquid without disturbing the DNA pellet .
Add 200µl 70 % ethanol and invert the tube twice to wash the pellet .
Centrifuge at 14,000rpm for 5 minutes .
Discard the supernatant and drain the tube on a piece of clean absorbent paper .
Allow to air dry for 15 minutes .
Add 50µl TE buffer to dissolve the DNA .
Rehydrate the genomic DNA by incubating at 55‐65°C for one hour .
Incubate overnight at room temperature to ensure complete genomic DNA hydration .
Store DNA at 4°C , for long term storage store at ‐20 or ‐80°C .
