Publications by authors named "Jonathan Royce"

2 Publications

  • Page 1 of 1

A novel primary amine-based anion exchange membrane adsorber.

J Chromatogr A 2011 Aug 4;1218(32):5386-92. Epub 2011 Apr 4.

Millipore Corp., 80 Ashby Road, Bedford, MA 01730, USA.

A novel anion exchange membrane adsorber is presented which shows excellent impurity removal under different buffer conductivities ranging from 2 to 2 7mS/cm. The membrane utilizes a primary amine ligand (polyallylamine) and was designed specifically to bind impurities at high salt concentrations. Studies with DNA, endotoxin, and virus spiked into buffer at varying salt conditions were done, resulting in clearance of >3, 4, and 4 LRV, respectively, with negligible change on increasing salt up to 27 mS/cm conductivities. Verification of virus removal in mAb feedstocks is also shown. The data are compared with other membrane adsorbers and a conventional resin which utilize traditional chemistries to demonstrate improved purification performance with the primary amine ligand. Additional data on scale-up of the membrane adsorber device is discussed. A stacked flat-sheet design was implemented to ensure linear scale-up of performance using bovine serum albumin (BSA) as a model. The linearly scalable device, coupled with the highly effective membrane for virus, DNA, and endotoxin removal, represents a step forward in polishing technology for the purification of monoclonal antibodies and recombinant proteins.
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http://dx.doi.org/10.1016/j.chroma.2011.03.068DOI Listing
August 2011

Practical application of the cake-complete, pore-plugging model for sizing normal flow filters.

Authors:
Jonathan T Royce

PDA J Pharm Sci Technol 2009 Sep-Oct;63(5):462-71

GE Healthcare Bio-Sciences Corp., 14 Walkup Drive, Westborough, MA 01581, USA.

Considerable process development efforts are spent selecting and sizing normal flow filters-typically beginning with small-scale experiments on flat sheet membrane samples and then scaling up to pleated membrane capsules and cartridges. Experimentally measuring filter capacity requires long test times; therefore, many scientists perform a short, small-scale test and fit the data to a mechanistic model which is used to extrapolate the filter's capacity. For more than a decade, the most commonly used fouling model has been the standard (or gradual pore-plugging) model. In 2006, Bolton et al. proposed a new model which combined both cake formation and complete pore-plugging (the "cake-complete" model). The authors used this model to fit data sets generated under constant flow and constant pressure conditions on microporous and ultrafiltration membranes. They concluded that the new model could more consistently predict filter performance as it was able to provide good fits of all data sets over a wide range of plugging behavior. This work describes a reliable method for solving the constant flow and constant pressure forms of the cake-complete model and for predicting the initial values of the plugging constants. Additionally, algorithms for determining required filter area to satisfy process conditions (batch volume and batch time) are proposed.
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March 2010
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