·                Excise the DNA fragment from the Agarose gel with a clean, sharp scalpel.

(Minimize the size of the gel by removing extra agarose).

·                Weigh the gel slice in a colourless tube. Add 3 volumes of Buffer QG to 1 volume of gel (100 mg~300µl).

·                Incubate at 50°C for 10 mins. to dissolve agarose. Vortexing in between helps (37°C is fine).

·                Add 1 gel volume of iso-propanol to the sample and mix (not for 500bp-4kb).

·                Place a QIAquick spin column in a provided 2 ml collection tube.

·                To bind DNA, apply the sample to the QIAquick column and centrifuge for 1min (maximum volume is 800µl, so do twice).

·                Discard flow-through and place QIAquick column back in the same collection tube.

·                Add 750µl Buffer PE to the column and centrifuge for 1min.

·                Discard flow-through and centrifuge the column for an additional 1 min. at 13,000 rpm.

·                Place the column into a clean 1.5ml eppendorf.

·                To elute DNA, add 30µl Buffer EB or H₂O to the centre of the QIA membrane and centrifuge for 1 min.

·                Can store at -20°C.