What length of fragment do you have? Why do you use PAGE instead of agarose gel, which makes the elution much easier?

Try using Gebaflex tubes for efficient elctroelution of DNA. Pls refer the attachement for oligo/DNA purification using GebaFlex tubes

if you've got this segment by PCR you just cut the segment from the PAGE, put it in eppndorf tube for 24h with 10µl water and do again a PCR with the same primers

first of all specify your question.you want to elute the fragment from the gel or u want to isolate the full length geneof the fragment. if it is simple isolation u need to follow a isolation kit like promega merck etc. if full length gene is concern u need to isolate RNA and use RACE pcr. Hope it would help u.

When you say you did not get the full length, what do you mean? Did you get nothing? Or something smaller? Howe are you eluting now?

So in general for PAGE, you can either use electroelution (more efficient, but often in a large volume with lots of salt) or passive elution (crush and soak - you can't get more than equilibrium). For either, you must first cut out your band of interest. For electroelution, use the recommended buffer for the apparatus (usually something like TBE). For crush and soak, add 4-5 gel slice volumes (estimate in a microfuge tube) of elution buffer. Ideally, your elution buffer should have a buffer (like Tris, etc - say 10-20 mM) and some monovalent ions (like NaCl or NaOAc). If you are going to ethanol precipitate in the next step, you might as well use 300 mM sodium acetate - then you won't need to add any additional salt later. If you think you have a degredation problem during elution (and that is why it isn't full length), you can add a little bit of SDS to your elution buffer to bother any contaminating DNases. If you ever elute RNA, add 1 mM EDTA.

After elution (4-5 hours to overnight) and before precipitation you MUST remove any remaining gel pieces. If your gel slice is in large pieces, you may be able to pipet the supernatant to a new tube. If the pieces are too small, you can use a biorad polyprep column or siliconized glass wool to remove acrylamide bits. If your DNA and acrylamide precipitate together, you end up with this horrid mess that either doesn't dissolve, or if it does dissolve, runs oddly on gels and probably won't work for anything else either.