24-Well Filter Plates Make Cell Culture Protein Purification Workflows A Breeze
24-well filter plates allow cell culture labs to process samples without leaving the 24-well format
December 2, 2021
While once only found in the highest throughput laboratories, the technology and equipment for automated cell culture is becoming more and more commonplace. Perhaps the most ubiquitous symbol of this trend has been the benchtop bioreactor, which has enabled many labs to do away with time and labor-intensive ‘one at a time’ cell culture in favor of a more automated, higher throughput format. Access to simplified cell culture automation has yielded great benefits, enabling scientists to explore greater numbers of cell types before selecting an individual strain, and performing a greater number of experiments in parallel.
Unfortunately, there is no such thing as a free lunch and this increase in cell culture capacity comes with a downside; a dramatic increase in the level of downstream processing required to clarify, sterilize, desalt, or otherwise manipulate the raw cell culture to clean up the output before it can be used in further experimentation. Given all of this, it is no surprise that the use of 24-well cell culture plates continues to grow at an estimated 14% per year, as more and more labs embrace this simple higher throughput option.
The protein purification workflow bottleneck
Until recently medium-throughput clarification of complex cell cultures to recover extracellular proteins still required a lot of manual steps, even in the 24-well plate format. Centrifugation could only be accomplished in individual spin columns, after which the supernatant had to be carefully removed by hand and samples passed one at a time through a syringe filter. A single 0.2 mm syringe filtration step would in some instances be sufficient, yielding a sterile solution ready for further study. However, in many cases, because the centrifugation step was not sufficient to fully clarify the supernatant, operators were forced to process their samples through a 0.45 mm syringe filter first to ensure the 0.2 mm sterilization filter did not clog, effectively doubling the workload. Further purification steps may then be required including concentration, desalting, and buffer exchange.
It is not hard to see how this manual manipulation quickly adds up to become a laborious and time-consuming process, not to mention fraught with opportunities for sample mix-up, errors, and contamination.
The benefits of 24-well filter plates
24-well filter plates enable users to filter cell culture products without leaving the 24-well format commonly used by many medium-scale labs with benchtop reactors. AcroPrepTM 24-well filter plates are essentially 24 individual filter membranes in the same footprint as a regular 24-well plate. On first inspection, they might look the same as regular 24-well plates, but a closer examination reveals the base of each well is composed of a porous filter membrane.
Instead of having to migrate samples from plate to spin column and back again, the user simply transfers the unfiltered cell culture material from a 24-well culture plate to a 24-well filter plate. The filter plate is set on top of a regular 24-well plate and the culture media is forced through the membrane using a centrifuge, vacuum manifold, or by positive pressure. The net result is the same, all the cells and other debris remain trapped in the filter plate and the clarified and sterile filtered supernatant is collected in a new 24-well plate. The entire operation requires only six pipetting operations with a multichannel pipette for the complete plate of 24 samples.
AcroPrep 24-well filter plates can perform a multitude of different functions.
The AcroPrep 24-well filter plate line offers an extensive range of membrane materials and pore sizes for clarification, sterile filtration, and clean-up of cell culture samples. AcroPrep 24-well filter plates support a range of applications for protein purification workflows including:
- Clarification and sterile filtration in a single filter plate
A multi-membrane filter plate that performs clarification and sterile filtration in a single operation, these plates combine a primary layer of Seitz® depth media that removes any cells and cell debris, followed by a 0.2 mm Supor filter for sterile filtration. This provides a huge time saving versus individually passing 24 samples through two separate syringe filters to achieve the same result manually.
- Minimized protein and nucleic acid binding
Using OmegaTM polyethersulfone (PES) membrane for ultrafiltration minimizes protein and nucleic acid binding for the effective concentration and purification of peptides, proteins, and oligonucleotides.
- Optimized protein purification for high yield
An exceptionally low protein binding PES Supor® membrane filtration optimized for applications such as protein purification, lysate clearance, and any other workflows when collecting the highest possible yield of protein in the supernatant is desired.
To better understand the benefits, you can expect by moving your spin column and syringe filter-based purification protocol over to a rapid, high volume 24-well filter plate-based format, read our Scientific Brief: From Cell Culture to Target Protein: Exploring the Benefit of the 24-Well Filter Plate Workflow.
Learn why other labs have already made the transition download the Scientific Brief.