Try our Urine Protein Concentration Calculator 

Viva Products - Protein Purification and Separation Technologies

Vivafree™ 2 Centrifugal Filter

Vivafree™ 2 Centrifugal Filter

Up to 2 ml starting volume
Rapid separation of free drugs and hormones

Vivafree™ 2 centrifugal filters offer fast, accurate separations of free drugs for Therapeutic Drug Monitoring. They have been used successfully for phenytoin1, valproic acid, antibiotics, immunosuppressants and other drugs. Vivafree™ filters are also being used clinically to separate free hormones such as testosterone and insulin. Separations can be performed as quickly as 20 minutes with high recoveries and excellent reproducibility. Savings of 35% have been reported when switching to Vivafree™ filters from another centrifugal ultrafiltration device2. Vivafree™ 2 filters are intended for in vitro diagnostic (IVD) applications and are designed for use in fixed angle rotors.

(1) Comparison of Centrifugal Filter Performance for Free Phenytoin Assays (PDF)

(2) Evaluation of a Centrifugal Filtration Device in the Measurement of Free Testosterone (PDF)

  • Separation of free hormones (testosterone, insulin, cortisol).
  • Sample preparation for therapeutic drug monitoring (phenytoin, valproic acid, antibiotics, immunosuppressants).
  • Remove proteins from samples before mass spectrometry.
  • Prepare samples for drug binding studies.
Device Type MWCO Test Sample
(all from serum)
Time Temp. Centrifugal
Force (x g)
Vivafree™ 500 125,000 Free Insulin 500 µl 150 µl 30 min. 37° C 2,000
Vivafree™ 500 30,000 Free Piperacillin 500 µl 100 µl 30 min. 25° C 2,500
Vivafree™ 500 30,000 Free Tazobactam 500 µl 100 µl 30 min. 25° C 2,500
Vivafree™ 500 30,000 Free Linezolid 500 µl 90 µl 20 min 37° C 1,000
Vivafree™ 500 30,000 Free Fluconazole 500 µl 90 µl 20 min. 37° C 1,000
Vivafree™ 2 30,000 Free Cortisol 500 µl 100 µl 20 min. 37° C 2,500
Vivafree™ 2 30,000 Free Phenytoin 1,000 µl 200 µl 20 min. 25° C 1,500
Vivafree™ 2 30,000 Free Testosterone 300 µl 100 µl 20 min. 37° C 4,500
Vivafree™ 2 30,000 Free Testosterone✝ 1000 µl✝ 500 µl 60 min. 25° C 4,500

* This sample starts with 1000 µl of diluted serum. Free Testosterone analyzed by mass spectrometry.

Note: Filtration times may vary according to sample volume and quality. Lipemic samples may require longer spin times. Filtration rates in swinging bucket rotors are typically 2-3 times slower compared to fixed angle rotors.

Concentrator Capacity
Swing Bucket Rotor 2 ml
Fixed Angle Rotor 2 ml
Total Length 125 mm
Width 16 mm
Active Membrane Area 0.95 cm²
Hold-up volume, membrane and support <10 µl
Dead stop volume (fixed angle rotor*) 55 µl (25° rotor)
Dead stop volume (swing bucket rotor*) No dead stop
Materials of Construction
Body Polycarbonate
Filtrate Vessel Polypropylene
Back Spin Vial Polypropylene
Concentrator Cap Polypropylene
O Ring Silicone
Membrane (ex 125,000 MWCO) Hydrosart®
Membrane (125,000 MWCO) Cellulose Triacetate
Equipment Required - Centrifuge
Rotor type Fixed Angle or Swinging Bucket✝
Rotor Cavity To fit 15 ml (17 mm) conical bottom tubes (95 mm depth)
Maximum speed
30,000 MWCO
5.000x g
Maximum speed
125,000 MWCO
2,500x g

✝ Filtration rates in swinging bucket rotors are typically 2-3 times slower compared to fixed angle rotors.

Description Buy
30,000 MWCO, Hydrosart Membrane, 25 per pack
Price: $165.00
30,000 MWCO, Hydrosart Membrane, 100 per pack
Price: $465.00
30,000 MWCO, Hydrosart Membrane, 500 per pack
Price: $2,000.00

How to Order

More Vivafree™ Centrifugal Filters

Our Products