|    | Data Sheet - PF723 > Product Catalogue | |
Millipore "V" Series Membranes -- for simple dialysis of small-volume sample |
Conventional cellulose dialysis sacs are routinely used to prepare microvolumes (---100µl) of protein or nucleic acid solutions for analyses. However, due to high surface-to-volume ratio and tedious handling characteristics, neither recoveries nor efficiencies are optimal with this method.
With the Millipore "drop dialysis" technique, a floating filter disc replaces the dialysis sac. This eliminates messy, unreliable "tying off" procedures. Because of the more open pore structure of these 0.025 or 0.05 µm Millipore membranes, diffusion of salts through the membrane is more rapid. In addition, depositing a 5 µl to 100 µl sample onto the membrane surface is less time consuming than cellulose dialysis bag procedures.
High Recoveries
Due to the small dialysis surface area required and the non-diffusion of the drop sample, exceptionally high recoveries are obtained. Marusyk and Sargeant have reported recoveries of DNA and protein samples in excess of 98%. (1)
A simple-to-use procedure
The Millipore "drop dialysis" technique is easy to use:
(1) Fill the bottom of the Petri dish with dialysate.
(2) Using stainless steel forceps, float the membrane filter disc (sidedness orientation of the ultrafiltration membrane will not impact performance) on the surface of the buffered solution. A tight-sealing dish will eliminate loss of sample to evaporation during the procedure.
(3) Deposit the sample (5-100 µl) on the center of the membrane with a micropipet. Use of marker dyes in the sample may help determine the dialysis of time required. Most samples are dialysed in less than 30 minutes.
(4) Recover the desalted sample with a micropipet.
Ordering Information
| Description | Catalogue No. |
| Millipore "V" Series Membranes, 0.025µm | |
| 13 mm, 100/pk | VSWP 013 00 |
| 25 mm, 100/pk | VSWP 025 00 |
| 47 mm, 100/pk | VSWP 047 00 |
| Millipore "V" Series Membranes, 0.05µm | |
| 13 mm, 100/pk | VMWP 013 00 |
| 25 mm, 100/pk | VMWP 025 00 |
| 47 mm, 100/pk | VMWP 047 00 |

