Using 96 Well Plates In High Throughput Laboratories

Using 96 well plates instead of autosampler vials has significant advantages for high throughput labs, due to the ease of automation. Unfortunately, not all steps in the process can be fully automated, but we will discuss our recommended instrumentation to use with 96 well plates in a high throughput lab for typical LCMS assays.

1. Positive Pressure Manifolds for Solid Phase Extraction

   Sample preparation instrumentation is essential to successful sample prep. In solid phase extraction (SPE), a vacuum manifold or positive pressure manifold is required to pull or push the solvents and analytes through the media. A major problem with conventional vacuum manifolds occurs as wells can run dry at different rates while the manifold pulls liquid through the SPE plate (or cartridges), allowing a free flow path for vacuum through the dry ports. In turn, this slows the flow in the remaining wells. The result is variation in column processing times, thus contributing to irreproducible analyte recoveries. In contrast, we recommend a positive pressure manifold for SPE processing, especially when using 96 well plates. The Chrom Tech Positive Pressure Manifolds have restricted-flow gas ports. These ports create superior flow control, so even if 95 out of 96 wells are empty, dry, or wet, the remaining single port will receive normal pressure to allow for easy processing. Our positive pressure manifolds are an efficient solution to viscous samples. The positive pressure manifold allows for gas pressures up to the supplied line pressure (typically 60-75 PSI), which supplies greater motive force for viscous sample flow. Adjusting the pressure up or down produces a column flow response that is smooth and immediate. If you’re interested in streamlining your SPE workflow, we always recommend the use of our Positive Pressure Manifolds for reproducibly consistent results.

2. The Dreaded Dry Down Step (read this if you can’t avoid this step!)

   The Porvair Concentrators/Evaporators for 96 well plates are the Chrom Tech recommendation for decreasing dry down/evaporation times. The Ultravap Mistral 96 well plate evaporator is the programmable evaporator we recommend for high throughput labs. At each programmed time stage, the scientist can determine the temperature of the Nitrogen, the flow rate of Nitrogen, and the depth of the needle above the plate (keeping the nitrogen just above liquid level helps decrease dry down time). We have seen customers cut dry down time in half with aqueous protein samples compared to other evaporators. Up to 15 password protected methods can be stored in the unit, making this ideal for high throughput labs.

3. Sealing the 96 well plate

   Sealing the 96 well plate is critical for LCMS assays to avoid cross contamination or laboratory contamination of the samples. There are many seal options out there, from silicone sealing mats to adhesive sealing films. But what if you want a seal that is easily pierced by a pipette tip? Chrom Tech recommends the UltraSeal Pro Thermal Plate Sealer for sealing many plates per day. One roll of foil can seal up to 4800 plates! With a password protected unit, only certain operators can change the temperature, duration, and force of the sealing. Users can simply press “Seal” and their plate is sealed with pre-existing specifications. Password protected methods are important for compliance and minimizing variables in the laboratory.

Our 96 Well Plate Instrument Trifecta!

When using 96 well plates in the analytical laboratory, using optimized instrumentation for the function is paramount. Reduce analysis time by using the Positive Pressure Manifold, UltraVap Mistral Evaporator and the UltraSeal Pro Thermal Plate Sealer. Contact Chrom Tech to talk with one of our product specialists to see if any or all of these instruments would improve your workflow!