Dry-compression packing of hydroxyapatite nanoparticles within a flat cuboid chromatography device and its use for fast protein separation.

We describe and discuss a simple dry-compression technique for preparing a flat cuboid chromatography device containing a shallow packed-bed of crystalline hydroxyapatite nanoparticles. We then discuss the use of this device for fast protein separation in the bind-and-elute mode. Such separation could be carried out at quite low pressures, making it possible to use inexpensive low pressure chromatography systems. In the flow rate range examined in this study, the pressure-drop across the device increased linearly with flow rate, indicating negligible media compaction during use. Using this device, binary protein mixtures could be separated in about a minute. Contrary to that observed in most packed-bed chromatographic separations, the width of the flow through and eluted peaks decreased with increase in flow rate. Therefore, both productivity and purity could be simultaneously increased by increasing flow rate. The suitability of this device for preparative protein separations was demonstrated by carrying out purification of a monoclonal antibody (Trastuzumab) from mammalian cell culture supernatant. This study opens up the possibility of developing dry-compression based flat cuboid packed-bed chromatography devices for fast preparative protein separation.