BUCHI Encapsulator B-395 Pro - Manual (Page 30)

5 Putting into operation
30 B-395 Pro Operation Manual, Version C
5 .5 Pumping systems
The Encapsulator B-395 Pro provides two systems for pumping the immobilization mixture:
• by volumetric syringe pump
• by air pressure from the pressure bottles
The syringe pump is mainly used:
1. For small volumes (< 60 mL).
2. Where the liquid flow rate has to be controlled very accurately on every run.
3. When a very low dead volume is needed (approximately 0.5 mL).
Pumping with air pressure is recommended:
1. When large volumes (> 60 mL) are needed.
2. When high flow rates are to be used for producing large beads, as would be the case when using
nozzles > 300 µm.
Both systems may be used with the concentric nozzle system. The core liquid is pumped with the
syringe pump and the shell liquid is pumped with air pressure. Of course, you may also use two air
pressure bottles by splitting the air line to the bottles with a “T” or “Y” connector.
5 .5 .1 Syringe pump
The syringe pump is used as a volumetric delivery system. It is a pump that very accurately delivers
the immobilization mixture. Most brands of plastic syringes can be used. (The use of glass syringes
is not recommended!) Each syringe type can be individually calibrated using the integrated syringe
calibration system (see chapter 6 “Operation”). The availability of pre-sterilized syringes makes aseptic
handling more convenient.
The pumping rate can vary from 0.01 mL/min to 50 mL/min depending on the syringe size.
a
Figure 5-16: Syringe pump
The syringe is attached to the bead producing unit with the luer lock fitting. The piston of the syringe is
pushed by the moving arm of the syringe pump a.