Comparison of chromatographic ion-exchange resins

Abstract

A comparative study was performed on strong cation-exchangers to investigate the pH dependence, efficiency, binding strength, particle size distribution, static and dynamic capacity, and SEM pictures of chromatographic resins. The resins tested included: SP Sepharose XL, Poros 50 HS, Toyopearl SP 550c, SP Sepharose BB, Source 30S, TSKGel SP-5PW-HR20, and Toyopearl SP 650c. Testing was performed with four different proteins: anti-FVII Mab (IgG), aprotinin, lysozyme, and myoglobin. Dependence of pH on retention was generally very low for proteins with high pI. An unexpected binding at pH 7.5 of anti-FVII Mab with pI < 7.5 was observed on several resins. Efficiency results show the expected trend of higher dependence of the plate height with increasing flow rate of soft resins compared to resins for medium and high-pressure operation. Determination of particle size distribution by two independent methods, Coulter counting and SEM, was in very good agreement. The mono-dispersed nature of Source 30S was confirmed. Binding to cation-exchange resins as a function of ionic strength varies depending on the specific protein. Generally, binding and elution at high salt concentration may be performed with Toyopearl SP 550c and Poros 50 HS, while binding and elution at low salt concentration may be performed with Toyopearl SP 650c. A very high binding capacity was obtained with SP Sepharose XL. Comparison of static capacity and dynamic capacity at 10% break-through shows in general approximately 50-80% utilisation of the total available capacity during chromatographic operation. A general good agreement was obtained between this study and data obtained by others. The results of this study may be used for selection of resins for testing in process development. The validity of experiments and results with model proteins were tested using human insulin precursor in pure state and in real feed-stock on Toyopearl SP 550c, SP Sepharose BB, and Toyopearl SP 650c. Results showed good agreement with experiments with model proteins.

Chromatography of proteins on charge-variant ion exchangers and implications for optimizing protein uptake rates

“…Table 2 shows the average diameter and standard deviation of each adsorbent along with the number of particles sampled, again showing the similarity of the particle size distributions around an average diameter of 109.6 μm. Staby et al [35] determined the particle size distributions of commercially available Toyopearl SP-650 C and SP-550 C and found them to be much wider, with a mean particle size of 80 μm for both adsorbents using Coulter counting and of 93 and 78 μm for SP-650 C and SP-550 C respectively using SEM. Transport modeling can account for the particle size distribution of the adsorbent [36][37][38], but the adsorbents studied here lie within sufficiently narrow distributions to allow monodispersity to be assumed.…”

Insights into Protein Sorption and Desorption on Dextran‐Modified Ion‐Exchange Media

“…The characteristics of SP Sepharose Fast Flow™ and SP Sepharose XL™, two resins differing mainly in that XL is modified with dextran extenders to increase functional group accessibility, along with Capto™ S, which is similar to XL, have been studied fairly extensively using the approaches and properties listed above, with the finding that the dextran extenders commonly can improve both equilibrium capacities and uptake rates of proteins [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21]. However, the dextran extenders can affect protein adsorption and transport processes in complex ways, for example, because of the ability of the dextran layer to expand and contract as a function of salt concentration [8] and the possibility for kinetic [11,20] and/or steric [20,21] exclusion effects depending on the conformation of the dextran and the electrostatic interactions between the protein and resin.…”

Fabrication of high-capacity protein ion-exchangers with polymeric ion-exchange groups grafted onto micron-sized beads by atom transfer radical polymerization

“…In the development of an ion-exchange chromatographic process for protein purification, the binding capacity of ion-exchange adsorbents is the most important index for evaluating the chromatographic performance. However, the binding capacity of representative ion-exchange beads remains at approximately 100 mg/mL [1][2][3]. Over the last several decades, the production of recombinant proteins, including monoclonal antibodies, has made significant strides in terms of product titer and yield due to recent breakthroughs in genetic engineering, bioreactor design and cell culture technology [4].…”

“…Typical base matrices used for protein chromatography include polysaccharides, hydrophilic polymers, metal oxides, and silica [5][6][7], where the inter-fiber spacing or pore diameter ranges from tens to over one hundred nanometers. The intraparticle diffusivities of proteins is always two magnitudes lower than those in free solution, leading to a protein binding capacity that is much lower than the adsorption capacity [2] .…”

“…Ion-exchange chromatography (IEC) is among the most popular purification techniques in the biopharmaceutical industry due to its high selectivity and resolution as well as its mild elution conditions [1]. In the development of an ion-exchange chromatographic process for protein purification, the binding capacity of ion-exchange adsorbents is the most important index for evaluating the chromatographic performance.…”