Vivaspin® 20 centrifugal concentrators offer increased volume flexibility and performance to the Vivaspin® potfolio. Vivaspin® 20 handles up to 20 ml in swing bucket rotors and 14 ml in fixed angle rotors accepting 50 ml centrifuge tubes. Vivaspin® 20 features twin vertical membranes for unparalleled filtration speed and >100-fold concentration. Volume graduation allows monitoring the concentration process and the modified dead stop pocket simplifies pipetting of the final concentrate. For higher process flexibility, Vivaspin® 20 is available with unique accessories and operating methods. For one-step desalting following concentration, a diafiltration cup filled with buffer is can be placed on the concentrator and spun another time to achieve 98% salt removal, instead of two spins to achieve the same result with the traditional refill and re-spin procedure. When an appropriate centrifuge is unavailable, or for single sample processing, for gas pressure filtration, Vivaspin® 20 can be filled with up to 15ml and then pressurised for bench top concentration. For even faster processing, gas pressure filtration can be combined with centrifugation. 'Pressure-fugation' is particularly useful for difficult or viscous samples such as serum, when using a low process temperature, or generally when minimum process time is essential. High flux PES membrane High retentate recovery > 90 % Vertical twin membrane for ultra-fast concentration Universal rotor compatibility Safe sample concentration due to dead-stop volume Convenient concentrate recovery by pipetting Volume graduation for easy reading/monitoring 100-fold concentration with twin vertical membranes Additional option for pressurized operation Rotor Compatibility Please note: Vivaspin® 20 (30 mm x 116 mm) is designed to fit into rotors that can accommodate Falcon 50 ml conical bottom tubes, e.g. Beckman Allegra 25R with TS-5.1-500 swing-out rotor with BUC 5 buckets and 368327 adaptors; Beckman TA-10.250 25° fixed angle rotor with 356966 adaptors; Heraeus Multifuge 3 S-R with (Heraeus/Sorvall) 75006445 swing out rotor with 75006441 buckets and adaptors for Falcon 50 ml conical bottom tubes. These devices are not designed to fit into rotors that only accept round bottom 29 mm x 105 mm tubes, e.g. Sorvall SS34 or Beckmann JA 20. If your rotor accepts only 29 mm x 105 mm round bottom tubes, please use the Vivaspin® Turbo 15, which can be used in either round bottom or conical centrifuge tubes Performance Characteristics

	Time to concentrate up to 30x [min.] at 20°C and solute recovery %
Mode	Centrifuge	Centrifuge	Bench top	Press-fuge
Rotor	Swing bucket	25° Fixed angle	Pressure	Swing bucket
Sart volume	20 ml	14 ml	10 ml	10 ml
	Min./Rec.	Min./Rec.	Min./Rec.	Min./Rec.
Cytochrome c 0.25 mg/ml (12,400 MW)
3,000 MWCO PES	110 / 97 %	180 / 96 %	60 / 96 %	- / -
BSA 1.0 mg/ml (66,000 MW)
5,000 MWCO PES	23 / 99 %	29 / 99 %	50 / 98 %	14 / 98 %
10,000 MWCO PES	16 / 98 %	17 / 98 %	32 / 97 %	8 / 97 %
30,000 MWCO PES	13 / 98 %	15 / 98 %	32 / 97 %	8 / 97 %
IgG 0.25 mg/ml (160,000 MW)
30,000 MWCO PES	27 / 97 %	20 / 95 %	46 / 94 %	13 / 97 %
50,000 MWCO PES	27 / 96 %	22 / 95 %	46 / 93 %	13 / 96 %
100,000 MWCO PES	25 / 91 %	20 / 90 %	42 / 88 %	12 / 94 %
Latex beads 0.004% in DMEM 10% FCS (0.055 µm)
300,000 MWCO PES	20 / 99 %	35 / 99 %	10 / 99 %	- / -
Latex beads 0.004% in DMEM 10% FCS (0.24 µm)
1,000,000 MWCO PES	4 / 99 %	12 / 99 %	4 / 99 %	- / -
Yeast 1.0 mg/ml (S. Cerevisiae)
0.2 µm PES	15 / 95 %	5 / 95 %	20 / 95 %	2 / 95 %