For 5 - 20mL samples, Vivaspin 20 centrifugal concentrators have been developed to offer increased volume flexibility and performance. It handles up to 20mL in swing bucket centrifuges and 14mL in 25° fixed angle rotors accepting 50mL centrifuge tubes. Featuring twin vertical membranes for unparalleled filtration speeds, it can achieve 100x plus concentrations. Remaining volume is easy to read off the printed scale on the side of the concentrator, and the modified dead stop pocket further simplifies direct pipet recovery of the final concentrate.
More process flexibility - Vivaspin 20 is available with unique accessories and operating methods that are designed to provide more process flexibility and further time saving.
Gas pressure filtration - When an appropriate centrifuge is unavailable, or for single sample processing, the concentrator can be filled with up to 15mL and then pressurized for bench top concentration. For even faster processing, gas pressure can be combined with centrifugal force. "Pressure-fugation" is particularly suitable for difficult or viscous samples such as serum, or when using a low process temperature which reduces filtration speed, and generally when minimum process time is essential.
One step desalting - In this procedure following concentration, a diafiltration cup is filled with buffer and then spun one time to achieve 98% salt removal. This compares to the need for two spins to achieve the same result with the traditional refill and re-spin procedure. The improved performance is due to the constant washing action of the buffer solution in the diafiltration cup as it replaces solvent and salts as they pass through the ultrafiltration membrane.