Amicon Spiral Cartridge Concentrator

Description - Operation - Cleaning - Storage - Sterilization - Testing - Limits

Description

Diaflo spiral cartridges are offered in four MW cut-offs and three sizes. They are especially useful for concentration or desalting (diafiltration) of proteins. They are not recommended for solutions containing suspended particles. Solutions should be pre-filtered (150 mesh, 100 µm) before flow processing. In the spiral cartridge, a "sandwich" of membrane layers is wrapped spirally around a permeate collection tube. Membrane layers in the sandwich are separated by a flow spacer which maintains the retentate flow channels at 0.8 mm (0.03 inch). It also enhances turbulence in the process stream to reduce fouling and gel formation. A cartridge may contain several such "sandwiches", depending on its size. The edges of the membranes are bonded together, so that the process solution cannot enter the flow channel where the fluid permeating the membrane is collected. This fluid moves spirally inside the membrane sandwich to the central permeate collection tube, and then out through the "header" assembly.

MW cut-offs

Solute	MW*	Membrane Type
Solute	MW*	Y3	Y10	Y30	Y100
Raffinose Bacitracin PVP-15 Cytochrome C alpha-Chymotrypsinogen PVP K-30 Albumin PVP-K60 PVP-K90 Gamma Globulin, Fraction II Dextran T-500 Apoferritin IgM	504 1,400 10,000 12,400 24,500 40,000 67,000 160,000 360,000 160,000-900,000 500,000 480,000 960,000	25 >80 - >98 >98 - >98 >98 >98 >98 >98 >98 >98	- 20 55 >95 >98 >80 >98 - - >98 - >98 >98	- - - 10 >95 60 >98 >90 - >98 - >98 >98	0 - - 0 10 20 20 65 >85 >95 - >95 >95
At 29 psi (1.9 bar)

Operation

Clean and rinse reservoir and tubing manually.
Using pure glycerin, lubricate O-rings. Do not use silicone or petroleum jelly. Place the two black rubber gaskets at both ends of the cartridge.
Place cartridge outlet side down on a firm surface (necessary to prevent telescoping of the cartridge). Using a slight twist motion, gently push permeate connector tube on inlet header of the ultrafiltration system into collection tube on inlet side of cartridge. Install the outlet header in the same way.
Secure both headers with stainless steel clamps. Do not overtighten clamps.
Fill process reservoir with 2 liters of 0.1 N NaOH. Close the drain valve, open the backpressure valve, direct permeate back to process reservoir. Switch pump to "forward". Turn pump on at mid-speed. Slowly close the backpressure valve until the typical operation pressure of 25-30 psi (1.7 - 2.0 bar) is reached. Recirculate for 10 minutes.
Drain system and repeat recirculation 2 x with dH₂O.
Drain system thoroughly. Fill reservoir with (prefiltered !) sample and start concentrating. Ratio can be monitored by the decrease in retentate volume. Never let the sample run completely through. Never let the cartridge run dry.
Monitor the system closely because pressure increases during the process of concentration.
Clean system after use.

For specific cleaning and storage solutions see below.

Cleaning

System Draining and Water Flush

Drain system promptly after use. Do not dry out the membrane.
With the cartridges still installed, flush the system immediately with clean water.
Drain the system completely.

Chemical Recirculation

Refill the system with 2 liters of an approved cleaning solution. Recirculate for 20 to 60 minutes at room temperature. Recirculation at 40°C to 50°C is possible, but cleaning solution with sodium hypochloride may only be used below 23°C.
Leave the permeate line open during operation. Direct the permeate back to the supply reservoir.
Drain the cleaning solution from the system. With permeate ports open, rinse the cartridges with two times with distilled or deionized water for 5 minutes at 25-30 psi (1.7 - 2.0 bar).
Flush system with fresh distilled or deionized water until permeate reaches neutral pH and all traces of cleaner are gone.
To check the effectiveness of the cleaning cycle, measure the distilled or deionized water flux.
To continue operation, fill system with next sample. If no more runs are planned, flush system with storage solution.

Cleaning Solutions

Reagent	Final Conc.	Volume	Mass
dH₂O		1800 ml
NaOH (MW 40.00)	0.1N		8 g

and/or one ore more of the following:

urea (MW 60.06)	6 M		721 g
NaCl (MW 58.44)	1 - 2 M		175 g
lab detergent (e.g. Sparkleen^®)	0.1 - 0.3 %	2 - 6 ml
sodium hypochloride (e.g. Chlorox Bleach: 5.25% by Wt.)	50 - 100 ppm	2 - 4 ml
nitric acid (HNO₃ 70%, 15.8 N, for metal ion removal)	0.05 N	6.33 ml

Adjust volume to 2 liter with dH₂O.

Storage

For up to 24 hours (interrupted run): Clamp and leave the system.
For up to 48 hours: Flush process fluid from the system, the clean the cartridge per recommended procedure. Refill the cartridge with distilled or deionized water (0.01 N NaOH may also be used) and clamp the system.
over 48 hours: Flush process fluid from the system, the clean the cartridge per recommended procedure. Refill the cartridge with distilled or deionized water plus 0.2% sodium azide. After cartridge is filled with storage solution, turn pump off and clamp the system. If possible, refrigerate the cartridges at 4°C. Do not use sodium hypochlorite as a storage solution.

Sterilization

recirculate 0.5% formaldehyde, 0.1 N NaOH and/or 50-100 ppm NaOCl (sodium hypochlorite at a maximum temperature of 23°C) or:
ethylene oxide (dry cartridges only)
- Chamber temperature: 125°F (52°C)
- Pre-vacuum: 27 '' Hg (700 mm)
- Conditioning: 15 minutes with live steam
- Gas pressure: 8 psig (0.6 kg/cm²g)
- Exposure time: 5 hours
- Humidity: 50%
- Post-vacuum: 27 '' Hg (700 mm)
- total cycle length: 7.25 hours
- Ethylene oxide: 12%
- %Diluent: 88%.

Testing

Integrity of the cartridge is determined by a simple test of the units permeate gas flow rate. A rate of less than 3 ml/min for S1 cartridges indicates a good-working unit. Cartridges with rates significantly higher should be suspect.
1. Clean the spiral cartridge thoroughly. Rewet cartridge with clean water, then drain housing.
2. Attach inlet line to a clean nitrogen gas or air supply. Close retentate side of the cartridge by closing the backpressure valve completely.
3. Pressurize inlet side with 5 PSIG, measure the permeate gas flow (liquid displacement technique).
4. Rewet cartridge when done.

Clogging of the cartridge can be tested by measuring the flux with destilled or deionized water. For the model S1YM10 cartridges under operating conditions (25-30 psi, 4°C) the water flux should be:
1. Recirculation flux > 1 liter / min. (back-pressure valve open, measure at retentate line)
2. Permeate flux > 300 ml / min. (back-pressure valve closed, measure at permeate line)

Limits (environmental resistance)

max. pressure for continuous operating: 60 psi (4.1 bar)
max. inlet/outlet pressure differential: 5 psi (0.3 bar)
pH limit: 3-11 (constant operation), 2-13.7 (cleaning)
max. operating temperature: 55°C

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