Molecular weight is a key property used in the characterization of polymer-based products. It refers to the molar mass distribution of polymer chains which can vary widely within polymers of the same chemistry. This can be problematic for regulated industries where products must conform to strict levels of consistency, such as the pharmaceutical sector.
Gel permeation chromatography (GPC) is an innovative method for determining the molecular weight distribution of a sample in solution. It is one of the leading methods for assessing the suitability and stability of pharmaceutical products and packaging materials. By sieving the dissolved sample through a column packed with porous media, compartments of distinct molecular weights elute through the solid phase at different speeds, causing the sample to differentially partition over time. The resulting data can be used to assess the lot to lot consistency of polymers.
The Importance of Novel GPC Columns
The GPC method can be used to assess the stability and quality of excipient ingredients and packaging materials used in pharmaceutical manufacturing. An array of complex polymer systems is used for tablet coatings, drug delivery systems, blister packaging, microfluidic vessels, and many more biopharmaceutical components. These include biological polymers such as proteins, naturally-derived carbohydrates, and synthetic polyolefins.
Polyolefins are the most broadly used synthetic polymer for medical and pharmaceutical packaging applications. Polyolefins often have broad molecular weight distributions with high polydispersity values. The molecular weight of polyolefins can vary by several orders of magnitude depending on their type and purpose. Measuring the molecular weight distribution of polyolefins through gel permeation chromatography requires an advanced high-temperature GPC system that can separate molecular compartments across a wide molecular weight range from 500, to upwards of 10,000,000.
RQM+ Lab Services has designed a tailored GPC column comprised of porous divinyl benzene particles of 13μm in size specifically for polyolefin analysis. These highly porous particles have been formulated into mixed bed columns suitable for high-resolution characterization of polyolefins for pharmaceutical packaging.
The 13 μm GPC column is accompanied by a range of high-resolution RQM+ Resolve DVB columns with a 5μm particle size. These provide greater resolution for specific molecular weight ranges.
Pharmaceutical Testing with RQM+ Lab Services
RQM+ Lab Services offers one of the leading molecular weight determination services in the US, with a selection of products optimized for the performance of GPC in the pharmaceutical sector. We explored the basics of molecular weight in our previous blog post: What is Polymer Molecular Weight?
If you would like more information on measuring the molecular weight distribution of polymer-based samples from pharmaceutical manufacturing, please do not hesitate to contact us.