Buffer exchange & sample preparation
The problem
Buffer exchange and sample concentration is part of everyday life for scientists working with antibodies and recombinant proteins. Whether it’s for sample prep, preparing for labeling or characterization, or developing formulation screening and optimization strategies for a biologic, the process is monotonous, labor-intensive, time-consuming, and prone to error.
Conventional buffer exchange methods like dialysis and centrifugal filtration suffer from inconsistency in results and are often hard to manage in larger numbers. Sample concentration is usually an additional time-consuming step required before downstream processing. Most methods require hands-on time, taking researchers away from other critical work.
The right tool for the job
Lil' Tuna is the first fully automated, plate-based benchtop buffer exchange system built for proteins, nucleic acids, and gene therapy vectors at any scale. Lil’ Tuna concentrates or exchanges 96- and 24-well plates for higher throughput or up to 6 individual samples in parallel — all on the same instrument. Its pressure-based ultrafiltration/diafiltration (UF/DF) approach keeps things flowing efficiently, tracks sample volumes and accurately adds buffer throughout the run, handling every step of the exchange cycle automatically from start to finish.
Lil’ Tuna uses a variety of consumables depending on your throughput needs. For higher throughput, there are plate-based consumables called Unfilters. All Unfilters use a regenerated cellulose membrane which minimizes non-specific binding. They come in 2 formats, 96-well (100 – 450 µL) or 24-well (0.45 – 8 mL). For single samples, there are individual sample wells called Unas. Each Una holds 0.45 to 8 mL of sample and Lil’ Tuna handles 1-6 Unas per run. Unas have either regenerated cellulose or polyethersulfone membranes allowing you to choose which works for your sample. Both Unfilters and Unas are designed to make sure your samples stay put, don’t get absorbed, and the liquid passes right through — with ≥96% recovery. So no matter what size the sample is or what volume is available, Lil’ Tuna has the right format.
Lil Tuna uses a UF/DF method with gentle orbital mixing that gives you consistent results without the drawbacks of dead-end ultrafiltration techniques. This matters because at high sample concentrations, the risk of aggregation goes up and proteins may gel at the membrane. Orbital mixing helps the sample flow faster and reduces the potential for aggregation.
The proof
Target the right formulation with tiny volumes in Unfilter 96
Finding the right excipients to keep your proteins happy is a challenge. Lil’ Tuna can do it using as little as 100 µL of each precious antibody sample. At this stage of formulation development these samples aren’t likely to run uniformly. Lil’ Tuna has you covered by constantly monitoring the volume and flow rate of each sample individually so it can exchange the slowpokes without letting the speedster wells go dry. If you want to concentrate them up to dosable levels at the end, Lil’ Tuna can do that too.
Fast pH screening and optimization with Unfilter 24
Screening for the optimal pH for your antibody is easier than ever before. It only takes 30 minutes to set up and you’ll be running your stability measurements in no time.
Buffer exchange with Unas
Whether you want to exchange 1 protein into 6 buffers, 6 different proteins into 1 buffer or anything in between, it only takes minutes to load up Lil’ Tuna and it's off to the races.
Lil' Tuna
Lil’ Tuna is the first automated, plate-based ultrafiltration and diafiltration (UF/DF) system for buffer exchanging, concentrating, or desalting proteins, viral vectors and nucleic acids - with consistently high recoveries. Process 1 to 96 samples in parallel with minimal hands-on time and achieve consistent and reliable sample prep for formulation screening, stability testing or any other downstream assay.
Want more info?
Want to learn more about how Lil' Tuna frees you up from buffer exchange?