All ligation protocols which I've found requires 10-20 ul reaction volume and 50-100 ng of vector or insert. When I purify the digested insert or vector from the gel, the concentration is always about 5 ng/ul. So It's impossible to do the ligation in 10-20 ul volume.
Can you help me with this? Can I do the ligation in bigger volume? How about the amount of DNA..could I use less insert or vector? I would like to use 6:1 or 3:1 molar ratio of insert to vector.