Begin by adding formaldehyde to a 1.8%final concentration to the tube containing the worms and rotating the tube at room temperature for six minutes. Then immediately freeze the tubes in liquid nitrogen, and store the samples at 80 degrees Celsius. To proceed thaw the formaldehyde cross-link sample in a room temperature water bath for three minutes, and rotate the samples for 16 minutes at room temperature.
At 1.25 molar glycine to a 125 millimolar final concentration, and rotate for five minutes at room temperature. Following this step, keep the samples on ice, or at four degrees, and use ice cold buffers until the magnetic bead elution. After centrifuging the sample at 1000 g for three minutes, wash it three times with one milliliter of PBSTX.
Then wash it two times with one milliliter of Resuspension Buffer. After the last wash, leave enough Buffer to ensure the total volume is at least three times the pellet volume and a minimum of 100 microliters.
