I use QIAGEN Plasmid Maxi kit to extract plasmid DNA from bacterial cells. In the final steps of the procedure I have to use a 30ml tube to elute the DNA with 15ml of buffer and then add 10.5ml of isopropanol to it to precipitate the DNA. Should I use plastic Flacon tubes or Glass tubes? I want the one with less DNA attachments to the tube so that I minimize the loss of DNA? Does DNA attach more to plastic or glass?!