EBA columns with a distribution system based on local stirring

Zafirakos, Elias; Lihme, Allan

doi:10.1007/978-94-017-1519-5_8

Cited by 5 publications

(14 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The turbulent zone increased from 8 cm to 12 cm (i.e., from 18% to 28% of the expanded bed height) and the numbers of theoretical plates decreased by 18% (Table II). This is consistent with the observations of Za®rakos and Lihme (1999), who found a correlation between mixing height (for a localised mixing distributor) and plate numbers.…”

Section: Discussionsupporting

confidence: 93%

“…The RFD is radically dierent from PPD distributors and from the local mixing design reported by Za®rakos and Lihme (1999) for columns of up to 40 cm diameter, described earlier (see the introduction). Furthermore, the diameter of the EBA column studied in this work is one of the largest so far reported.…”

Section: Discussionmentioning

confidence: 99%

“…In these designs,¯uid enters through one or more inlets in the column base or located radially around the column wall. In addition, a localized mixing (LM) device is positioned on the base (Za®rakos and Lihme, 1999) to create a well-mixed region (e.g., 20 cm high in a 40-cm diameter column with rotation at 30 rpm) in the lower section of the column where the¯uid is applied. In this way, it is hoped that the entering¯uid is evenly distributed and channeling or jetting into the stable section of the bed above is prevented.…”

Section: Introductionmentioning

confidence: 99%

“…One of the main factors likely to aect scaleability is the size of the mixing zone, and the results of Za®rakos and Lihme (1999) suggest that as column diameter is increased, it may be dicult to localize mixing to a small region of the bed while still achieving adequate¯uid distribution. The authors concluded that increasing the height of settled matrix could be used to control the percentage of the expanded bed taken up by the mixing zone.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

A new fluid distribution system for scale‐flexible expanded bed adsorption

Hubbuch

Heebøll-Nielsen²,

Hobley³

et al. 2002

Biotech & Bioengineering

View full text Add to dashboard Cite

A new fluid distribution system designed for expanded bed adsorption was introduced and studied in a 150-cm diameter column. Based on fluid application through a rotating distributor, it eradicates the need for perforated plates, meshes, or local mixers. The effect of rotation rate on column performance was examined by fluidizing a 30-cm high bed of supports with tap water and introducing pulses of dye or acetone tracer. Linear bed expansion was seen as the superficial fluid velocity was raised from 170 x h(-1) to 450 cm x h(-1) (3000 L x h(-1) to 8000 L x h(-1)), and there was little change in expansion characteristics as distributor rotation rate was increased from 2.5 to 10 rpm. The distributor was observed to generate a flow pattern suitable for expanded bed adsorption when the supports were fluidized at a superficial fluid velocity of 283 cm center dot h(-1) and dye pulses introduced. At a rotation rate of 2.5 rpm, no significant dead zones were observed, and a discrete band was formed that moved up through the bed. Furthermore, the pattern of dye movement could be used to calculate interstitial linear fluid velocities of 460 cm x h(-1) and 572 cm x h(-1) at the column wall and center, respectively, indicating a parabolic flow profile. The distributor rotation rate giving the best operating conditions was found to be 2.5 rpm when the bed was fluidized at a flow velocity of 283 cm x h(-1) and the residence time distribution of acetone tracer examined. Under these conditions, the coefficient of axial dispersion was 6.1 x 10(-6) m(2) x s(-1) and 29 theoretical plates were measured. When the rotation rate was raised to 10 rpm, the coefficient of axial dispersion increased to 8.08 x 10(-6) m(2) x s(-1) and the number of theoretical plates decreased to 22.

show abstract

Section: Discussionsupporting

confidence: 93%

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

A new fluid distribution system for scale‐flexible expanded bed adsorption

Hubbuch

Heebøll-Nielsen²,

Hobley³

et al. 2002

Biotech & Bioengineering

View full text Add to dashboard Cite

show abstract

“…A very different design (UpFront Chromatography A/S, Copenhagen, DK) uses a stirring device at the column base with feed introduced above a restriction mesh (Lihme et al, 2000;Zafirakos and Lihme, 1999). When a crude potato juice extract was processed with this design, a combination of filtration and gravity sedimentation was needed to reduce the concentration and size of solids in the feed (Straetkvern et al, 1999).…”

Section: Introductionmentioning

confidence: 99%

Compatibility of column inlet and adsorbent designs for processing of corn endosperm extract by expanded bed adsorption

Menkhaus

Glatz²

2004

Biotech & Bioengineering

View full text Add to dashboard Cite

Corn has emerged as a viable host for expression of recombinant proteins; targeted expression to the endosperm has received particular attention. The protein extracts from corn endosperm differ from those of traditional hosts in regard to the nature of residual solids and extracted matrix contaminants. Each of these differences presents reasons for considering expanded bed adsorption for product capture and new considerations for limitations of the method. In this work three inlet-flow distribution devices (mesh, glass ballotini, and localized mixing) and six adsorbents with different physical (size and density), chemical (ligand), and base matrix properties were evaluated to determine conditions compatible with processing of crude corn endosperm extract by expanded bed adsorption.Of the inlet devices evaluated, the design with localized mixing at the inlet (as produced commercially by UpFront Chromatography A/S, Copenhagen, DK) allowed solids up to 550 Am into the column without clogging for all flow rates evaluated. A mesh at the inlet with size restriction of either 50 Am or 80 Am became clogged with very small corn particles (< 44 Am). When glass ballotini was used, large particles (550 Am) passed through for high flow rates (570 cm/h), but even small (< 44 Am) particles became trapped at a lower flow rate (180 cm/h). The physical and chemical properties of the resin determined whether solids could be eluted. The denser UpFront adsorbents allowed for complete elution of larger and more concentrated corn solids than the currently available Amersham Streamline adsorbents (Amersham Biosciences, Piscataway, NJ) as a result of the former's higher flow rate for the desired 2Â expansion (570 cm/h for UpFront vs. 180 cm/h for Streamline). All corn solids < 162 Am eluted through nonderivatized UpFront resin. Larger corn solids began to accumulate due to their elevated sedimentation velocities. Feeds of < 44 Am solids at 0.45% and 2.0% dry weight successfully eluted through ion exchange adsorbents (DEAE and SP) from UpFront. However, significant accumulation occurred when the solids size increased to a feed of < 96 Am solids, thus indicating a weak interaction between corn solids and both forms of ion exchange ligands. Expanded beds operated with Streamline ion exchange adsorbents (DEAE and SP) did not allow full elution of corn solids of < 44 Am. A hyperdiffuse style EBA resin produced by Biosepra (Ciphergen Biosystems, Fremont, CA) with CM functionality showed a severe interaction with corn solids that collapsed the expanded bed and could not be eliminated with elevated flow rates or higher salt concentration. B 2004 Wiley Periodicals, Inc.

show abstract

Antibody Capture from Corn Endosperm Extracts by Packed Bed and Expanded Bed Adsorption

Menkhaus

Glatz

2008

Biotechnol Progress

View full text Add to dashboard Cite

Topical treatments of chronic infections with monoclonal antibodies will require large quantities of antibodies. Because plants have been proven capable of producing multisubunit antibodies and provide for large-scale production, they are likely hosts to enable such applications. Recovery costs must also be low because of the relatively high dosages required. Hence, we have examined the purification of a human secretory antibody from corn endosperm extracts by processing alternatives of packed bed and expanded bed adsorption (EBA). Because of the limited availability of the transgenic corn host, the system was modeled by adding the antibody to extracts of nontransgenic corn endosperm. Complete clarification of a crude extract followed by packed bed adsorption provided antibody product in 75% yield with 2.3-fold purification (with antibody accounting for 24% of total protein). The small size of the packed bed, cation-exchange resin SP-Sepharose FF and the absence of a dense core (present in EBA resins) allowed for more favorable breakthrough performance compared to EBA resins evaluated. Four adsorbents specifically designed for EBA operation, with different physical properties (size and density), chemical properties (ligand), and base matrices were tested: SP-steel core resin (UpFront Chromatography), Streamline SP and Streamline DEAE (Amersham Biosciences), and CM Hyper-Z (BioSepra/Ciphergen Biosystems). Of these, the small hyperdiffuse-style resin from BioSepra had the most favorable adsorption characteristics. However, it could not be utilized with crude feeds due to severe interactions with corn endosperm solids that led to bed collapse. UpFront SP-steel core resin, because of its relatively smaller size and hence lower internal mass transfer resistance, was superior to the Streamline resins and operated successfully with application of a crude corn extract filtered to remove all solids of >44 microm. However, the EBA performance with this adsorbent provided a yield of only 61% and purification factor of 2.1 (with antibody being 22% of total protein). Process simulation showed that capital costs were roughly equal between packed and expanded bed processes, but the EBA design required four times greater operating expenditures. The use of corn endosperm as the starting tissue proved advantageous as the amount of contaminating protein was reduced approximately 80 times compared to corn germ and approximately 600 times compared to canola. Finally, three different inlet designs (mesh, glass beads, and mechanical mixing) were evaluated on the basis of their ability to produce efficient flow distribution as measured by residence time distribution analysis. All three provided adequate distribution (axial mixing was not as limiting as mass transfer to the adsorption process), while resins with different physical properties did not influence flow distribution efficiency values (i.e., Peclet number and HETP) when operated with the same inlet design.

show abstract

EBA columns with a distribution system based on local stirring

Cited by 5 publications

References 1 publication

A new fluid distribution system for scale‐flexible expanded bed adsorption

A new fluid distribution system for scale‐flexible expanded bed adsorption

Compatibility of column inlet and adsorbent designs for processing of corn endosperm extract by expanded bed adsorption

Antibody Capture from Corn Endosperm Extracts by Packed Bed and Expanded Bed Adsorption

Contact Info

Product

Resources

About