[Skip to Content](https://www.sigmaaldrich.com#main-content)
[](https://www.sigmaaldrich.com/US/en)
Products
Cart0
USEN
Products
ProductsApplicationsServicesResourcesSupport
[Login / Register](https://www.sigmaaldrich.com/oidc-sign-in)
[Order Lookup](https://www.sigmaaldrich.com/US/en/order-lookup)
[Quick Order](https://www.sigmaaldrich.com/US/en/quick-order)
Cart0
[Home](https://www.sigmaaldrich.com/US/en)[Sample Purification](https://www.sigmaaldrich.com/US/en/applications/analytical-chemistry/sample-preparation/purification)Setting Pressure Limits for Size Exclusion Chromatography
# Setting Pressure Limits for Size Exclusion Chromatography
Pressure is generated by the flow through the chromatographic system. For optimal chromatography functionality, it is important to understand the principle of the pressure drop over the different parts of a system (Fig 1.11).

__Figure 1.11.__Example of the pressure in different parts of a system during run of a column. Note that the pressure values are only used to illustrate the principle.
- ∆pbefore does not affect the column.
- The pressure on the column hardware is the sum of ∆pafter and ∆p. Do not exceed the column hardware limit!
- ∆p is individual and needs to be determined for each column.
For more information, refer to the ÄKTATM Laboratory-scale Chromatography Systems Instrument Management Handbook, 29-0108-31.
To protect the column hardware and the packed bed of the chromatographic medium, it is important to set limits that must not be exceeded during the run. There are two important pressure limits that must be taken into consideration:
1. __To protect the column hardware:__ Column hardware pressure limit (Fig 1.12), which is the maximum pressure the hardware can withstand without being damaged. This value is fixed for each column type. Leakage from the column could be a sign of excessive pressure on the column hardware. The column hardware pressure limit is included in the instructions and in UNICORN™ column list for each column type, respectively.

__Figure 1.12.__Column hardware pressure limit is the maximum pressure the column can withstand without damage.
2. __To protect the packed bed:__ Delta pressure (Δp) or maximum pressure over the packed bed is the maximum pressure the packed bed of chromatography medium can withstand without risking gap formation (Fig 1.13) or bed collapse. This value varies depending on conditions. A typical value for Δp or maximum pressure drop over the packed bed is provided for each column type in the instructions and UNICORN column list. Note however that Δp is individual for each column and needs to be determined. The procedure for doing this is described in Instructions 29-0272-71. The packed bed is best protected by controlling the flow rate. Use lower flow rates for high-viscosity solutions and/or low temperature (Table 1.3).
TemperatureFlow rate (ml/min)
20 ºC to 25 ºCMaximum flow rate, water
Maximum flow rate, 20% ethanol1.5
0.75
4 ºC to 8 ºCMaximum flow rate, water
Maximum flow rate, 20% ethanol0.75
0.35
Table 1.3. Example of flow rate limits at different viscosity and temperature, Superose 6 Increase 10/300 GL

__Figure 1.13.__The maximum pressure over the packed bed is the maximum pressure the packed bed of chromatography medium can withstand without gap formation. This is not a fixed value.
* * *
## Materials
Sorry, an unexpected error has occurred
Response not successful: Received status code 500
__Related Articles__
- [Maintenance of Multimodal Chromatography Media and Storage Conditions](https://www.sigmaaldrich.com/US/en/technical-documents/protocol/protein-biology/protein-purification/maintenance-of-media-and-storage-conditions)
- [Selection of Purification Equipment](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/analytical-chemistry/purification/appendix4)
- [Bind/Elute vs Flowthrough Mode in Multimodal Chromatography](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/analytical-chemistry/purification/bind-elute-vs-flowthrough-mode-in-multimodal-chromatography)
- [Chiral Chromatography Frequently Asked Questions](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/analytical-chemistry/purification/faq)
- [FastWoRX for Faster and Greener Alternative to Liquid-Liquid Extraction](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/analytical-chemistry/purification/fastworx)
- [High Purity Carbon Adsorbents for Chromatography](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/analytical-chemistry/purification/high-purity-carbon-adsorbents)
- [Plasmid purification by ion exchange chromatography with Genopure kits](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/analytical-chemistry/purification/ion-exchange-chromatography)
- [LRA (Lipid Removal Agent) for Biopharmaceutical Production](https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/analytical-chemistry/purification/lra-lipid-removal)
- [View More](https://www.sigmaaldrich.com/US/en/search/facet-search?focus=sitecontent&term=facet-search)
Top
__Sign In To Continue__
To continue reading please sign in or create an account.
Sign In__Don't Have An Account?__Register
Support[Customer Support](https://www.sigmaaldrich.com/US/en/support/customer-support)[Contact Us](https://www.sigmaaldrich.com/US/en/collections/offices)[FAQ](https://maestro.my.site.com/knowledgeportal/s/)[Safety Data Sheets (SDS)](https://www.sigmaaldrich.com/US/en/documents-search?tab=sds)[Certificates (COA/COO)](https://www.sigmaaldrich.com/US/en/documents-search?tab=coa)[Quality & Regulatory](https://www.sigmaaldrich.com/US/en/life-science/quality-and-regulatory-management)[Calculators & Apps](https://www.sigmaaldrich.com/US/en/support/calculators-and-apps)[Webinars](https://www.sigmaaldrich.com/US/en/collections/webinars)
Orders[Order Lookup](https://www.sigmaaldrich.com/US/en/order-lookup)[Quick Order](https://www.sigmaaldrich.com/US/en/quick-order)[Custom Products](https://www.sigmaaldrich.com/US/en/services/custom-products)[eCommerce Solutions](https://www.sigmaaldrich.com/US/en/life-science/ecommerce/ecommerce-solutions)
Company[About Us](https://www.sigmaaldrich.com/US/en/life-science/about-us)[Responsibility](https://www.sigmaaldrich.com/US/en/life-science/ssbi)[Events](https://www.sigmaaldrich.com/US/en/collections/events)[Press Releases](https://www.sigmaaldrich.com/US/en/collections/press)[Programs](https://www.sigmaaldrich.com/US/en/life-science/partnership-programs)[Careers](https://careers.merckgroup.com/global/en)[Offices](https://www.sigmaaldrich.com/US/en/collections/offices)
Social Media
[](https://www.linkedin.com/company/merck-life-science)
[](https://x.com/Merck_lifesci)
[](https://www.facebook.com/Merck.lifescience)
[](https://www.instagram.com/mercklifescience/)
[](https://www.youtube.com/@MerckLifeScience/featured)
MilliporeSigma
__Research. Development. Production.__
We are a leading supplier to the global Life Science industry with solutions and services for research, biotechnology development and production, and pharmaceutical drug therapy development and production.
[](https://www.sigmaaldrich.com/US/en)
[Sigma-Aldrich® Solutions](https://www.sigmaaldrich.com/US/en/life-science/sigma-aldrich)[BioReliance® Solutions](https://www.sigmaaldrich.com/US/en/life-science/bioreliance)[Millipore® Solutions](https://www.sigmaaldrich.com/US/en/life-science/millipore)[SAFC® Solutions](https://www.sigmaaldrich.com/US/en/life-science/safc)[Milli-Q® Solutions](https://www.sigmaaldrich.com/US/en/life-science/milliq)[Supelco® Solutions](https://www.sigmaaldrich.com/US/en/life-science/supelco)
© 2026 Merck KGaA, Darmstadt, Germany and/or its affiliates. All Rights Reserved, including Text and Data Mining for AI training and similar technologies.
Reproduction of any materials from the site is strictly forbidden without permission.
[Site Use Terms](https://www.sigmaaldrich.com/US/en/life-science/legal/site-use-terms)|[Privacy Policy](https://www.sigmaaldrich.com/US/en/life-science/legal/privacy-statement)|[General Terms and Conditions of Sale](https://www.sigmaaldrich.com/US/en/life-science/legal/terms-and-conditions)|[Copyright Consent](https://www.sigmaaldrich.com/US/en/life-science/legal/copyright-consent) |[Site Map](https://www.sigmaaldrich.com/US/en/site-map)
An unknown error has occured.