Our PCR product purifications enzymatically remove leftover primer and dNTP’s that would otherwise interfere with subsequent sequencing reactions. (Requesting PCR purification will not delay your sequencing results.)
We highly recommend verifying the length and concentration of your fragments before sending them to us. Doing so can potentially save you time if there is a possibility that your PCR amplifications are very weak or fail. Running your PCR’s on a gel would also alert you to the presence of spurious amplification products.