Unique selectivity windows using selective displacers/eluents and mobile phase modifiers on hydroxyapatite

Isolation and purification of recombinant proteins, antibodies and plasmid DNA with hydroxyapatite chromatography

“…Endotoxins, host cell DNA and enveloped viruses are strongly retained by HA and typically are only released during column regeneration [5]. Finally, the material is known to distinguish clearly between native and denatured variants of the same protein [6] as well as between monomers, dimers and aggregates [7,8]. The sensitivity of HA towards acidic conditions can, as in the case of tooth enamel, be ameliorated by exchanging some of the hydroxy groups in the structure for fluoride [9].…”

“…In addition, the antibody is eluted at a lower conductivity, which improves the compatibility of the HA step, for example, with a subsequent ion-exchanger step. A detailed study of the interaction of molecules incorporating positively charged, metal chelating and/or hydrogenbonding groups as a function of different mobilephase modifiers, including phosphate, sulfate, lactate and borate can be found in [7,24]. Finally, the interaction of certain natural HA-binding proteins, such as statherin may be of interest in the interpretation of protein-HA interactions [3].…”

Sample displacement chromatography as a method for purification of proteins and peptides from complex mixtures

“…Ion-exchange (IEC) and different affinity chromatography (AC) methods are most frequently employed for the isolation of biologically active therapeutic proteins [23, 24], but there are additional chromatographic methods, such as hydrophobic-interaction chromatography (HIC) and hydroxyapatite chromatography, that are increasingly being used [25–27]. Reversed-phase chromatography (RPC) has been less frequently used for the separation of therapeutic proteins because of the potential for denaturation and loss of biological activity of target components after elution with organic solvents [28].…”

To catch a thief: Opening a CTO and its effect on the contralateral donor artery FFR

“…Hydrogen bonding with the resin's hydroxyl groups and anion exchange with the resin's calcium sites can also occur, however, these interactions are thought to play a less important role for protein adsorption in CHT (Ng et al, 2007, 2008). The presence of different mobile phase modifiers, such as sodium phosphate, have also been shown to play a critical role in separations on CHT (Gagnon et al, 2006; Gorbunoff, 1984b; Gorbunoff and Timasheff, 1984c; Morrison et al, 2010).…”

“…Mass action selective displacers operate by having an affinity for the resin which lies between that of the two solutes being separated, and their efficacy can be readily predicted using the steric mass action formalism (Brooks and Cramer, 1992, 1996). While selective displacement chromatography has been successfully employed in ion exchange systems (Barnthouse et al, 1998; Gadam and Cramer, 1994; Gallant et al, 1996; Jayaraman et al, 1993, 1995; Kundu et al, 1995, 1997; Ladiwala et al, 2003; Liu et al, 2006; Mazza et al, 2002; Moore et al, 2005; Rege et al, 2004; Shukla et al, 1998; Tugcu et al, 2002, 2003), to date only a preliminary study has been carried out in hydroxyapatite resin systems (Morrison et al, 2010).…”