30] Preparation of calcium phosphate gel deposited on cellulose

Abstract

Publisher Summary This chapter discusses reagents and procedure employed for the preparation of calcium phosphate gel deposited on cellulose. Prior to packing columns of the gel–cellulose, it is very important to remove dissolved gases by evacuating the suspension with a water aspirator for about half an hour after equilibration to the chosen temperature. To a suitable glass chromatographic tube, fitted with a detachable sintered glass plate covered with a circle of filter paper, is added the appropriate buffer. Slurry of the gel–cellulose is added in a few portions to the tube. The gel–cellulose is allowed to pack by gravity and is equilibrated with appropriate buffer by washing it with several volumes of the buffer at the selected temperature. By using about 100 ml of gel-cellulose in a column, 4.2 cm in diameter, a flow rate of about 20–30 ml per hour is obtained. For the purification of some enzymes, it is required that the gel–cellulose be aged. In contrast, purification of the α -ketoglutarate dehydrogenase complex from extracts of pig heart requires that the gel–cellulose should be less than one month old.