The AKTA FPLC Chromatographic System is a re-design of the classic Pharmacia FPLC instrument, the gold standard in protein purification for over 20 years. The new system is build around the AKTA Design platform common for all of the GE Healthcare chromatographic instruments, from low-pressure AKTAPrime to the high-performance AKTAPurifier. The new FPLC instrument is more compact than its predecessor and offers two times the maximum flow rate (20 ml/min). The system accepts a wide variety of custom and pre-packed columns and can perform all the chromatographic steps employed in modern protein purification (from affinity to gel filtration), but the most popular applications of this system lie with high-resolution, Mono bead media. The high flow rate and pressure limit of 5 MPa allows for rapid (i.e. 10-20 min), high-resolution separations using Resource or Mono columns. The system comes standard with a UV/conductivity monitor (UPC-900), that enables the use of an optional pH probe.
AKTAFPLC is controlled through UNICORN software and can be run on a PC platform. UNICORN is mostly menu-driven and menus can be prompted by clicking on an area (e.g. pump) of the FPLC schematic present in the Run window. The schematic itself is easy enough to read, but graphically, it is a throwback to Windows 3.1. Suitable animations, featuring a photographic likeness of FPLC parts, could have significantly cut learning time for new users considering that the system comes with several volumes of manuals (offering a varying degree of detail). Operating FPLC under UNICORN is reasonably straightforward, although occasionally useful menu options are buried rather deep. The software has a superficial resemblance to the AKTA PrimeView, but while PrimeView serves merely to record the run, UNICORN actually controls the run and offers a number of options to simplify purification procedures (such as automatic detection and collection of peak fractions). Using UNICORN, FPLC can be either manually run or using pre-programmed methods. In addition, the operator can also employ the method wizard to systematically vary parameters, select columns from the library, or a variety of other options.
The flexibility of the system is further expanded by employing various accessories, such as Superloops, column racks, and different optics/filters for the UV monitor. FPLC accepts a wide variety of pre-packed column formats, from HiTrap and HiLoad to Tricorn, Resource and Mono, as well as a number of custom or user-packed columns. In our lab, we have been using the Academic Edition AKTA FPLC (pump P-920, monitor UPC-900 and fraction collector Frac-950) and so far, the performance has been outstanding for separations, particularly when using high resolution media like Resource and Mono. We currently use 2 of different racks for various fraction sizes; Rack A accepts 30 mm (50 ml Falcon) and 18 mm (12 ml cell culture) tubes for large scale preps, while Rack B accepts 12 mm tubes (we use it with optional adapters and 1.5 ml Eppendorf tubes) for smaller scale purifications. There are additional racks available, which expand the collection options from 96-well plates to 250 ml bottles. As is the case with other aspects of the system, the versatility and flexibility in fractionation is quite impressive. From a purely logistical point of view, I liked the fact that the injection valve and monitor are not firmly fixed to the case, facilitating work within the confines of a chromatographic refrigerator (makes a lot of difference when changing the columns or loading the injection loop).
Vladimir Svetlov, PhD
Research Scientist
Department of Microbiology
Ohio State University