Question #1: What is the material or solute that you are concentrating or drying?

Is it biological or non-biological? We generally break solutes into two categories – biological (DNA, RNA, enzymes, proteins, vaccines, etc.) and non-biological (products of organic synthesis, drug metabolites, pesticides).

The sample concentration and drying technique of choice for non-biologicals is vacuum evaporation. These samples are generally in high concentrations of organic solvents and/or strong acids and bases. Vacuum concentration offers rapid concentration of non-biological materials. The main question with biologicals is whether to freeze dry (lyophilize) or vacuum concentrate. Freeze drying is generally recommended when the material is to be stored for long periods of time, must be easily and quickly reconstituted, and needs to retain biological activity (i.e., proteins/enzymes). Most molecular biology applications involving DNA/RNA, in aqueous or aqueous + low concentration organics, use vacuum concentration for sample prep. Consider systems such as the Thermo Scientific™ Savant™ SpeedVac™ DNA130 or SPD1030.

Freeze drying can be performed efficiently in a vacuum concentrator. However, freeze drying requires a deep vacuum (i.e., rotary vane oil pump) to keep the sample frozen during sublimation. Depending on the solute/ solvent and conditions, a properly configured SpeedVac system can be used for either freeze drying or vacuum concentration such as the SpeedVac SPD120P2.

Question #2: What is the solvent that your material is prepared in?

If it is an organic solvent, is it an aggressive solvent (methylene chloride, toluene), or a non-aggressive solvent (ethanol, methanol, acetonitrile) or a high-boiling-point solvent (DMSO, DMF)? This is one of the most important decision making factors in the proper choice of a SpeedVac system. Our goal is to give you the most cost-effective solution to your sample prep needs. Due to the need to withstand an increasingly harsh environment, the cost of a SpeedVac concentrator increases with the harshness of the solvent as follows:

Aqueous < Non-aggressive organics < Aggressive organics < Strong acids/bases

A SpeedVac system designed for use with strong acids/ bases would be suitable for use with other solvents such as non-aggressive organics, aggressive organics or aqueous. Consider systems such as the Thermo Scientific Savant SpeedVac SPD140DDA P1 or PSD300DDA P1. However, if you were only using aqueous or low concentration non-aggressive organics, you may not want to look at systems such as Thermo Scientific Savant SpeedVac SPD1030 or SPD2030.

By considering your solvent(s) to be evaporated, you can select the SpeedVac that will meet your needs most cost effectively. (Be sure to consider your future needs; see also question 6.)

Question #3: What type of vessels will be used? What is the sample volume and the number of samples to be processed?

Thermo Scientific Savant offers SpeedVac systems and rotors capable of processing a wide variety of sample volumes and containers. Determine your format, working volume and number of tubes/plates or flasks, and this will help determine which size of system meets your needs; large capacity or small capacity.

Question #4: Do you want a fully integrated system or a modular system?

Thermo Scientific Savant pioneered integrated technology for vacuum concentration. Our fully integrated SpeedVacs feature all components integrated into one compact system, optimized for performance, and factory tested to ensure your system is free of vacuum leaks. You take it out of a box, plug it in and you’re done. Integrated systems include the DNA130 and SPD1030.

The only potential disadvantage of the integrated systems is flexibility to upgrade as your needs in the lab changes. Modular systems flexible design allows you to change components of the system should you need to add a secondary cold trap or different vacuum pump as the labs applications changes. A component system can be easily upgraded. Savant SpeedVac kits are available to make it easy to order a complete module system such as the SPD120P2, SPD210DXL, DNA140DDAP1 and SPD300DDAP1 include SpeedVac system, cold trap, vacuum pump and rotor.

Question #5: Do you want oil-free or oil vacuum pump technology?

Any component SpeedVac system can be configured with either an oil-free diaphragm pump or rotary vane oil pump. We generally recommend oil-free technology for all applications except freeze-drying (which requires the deeper vacuum achieved with an oil pump) and evaporation of high-boiling-point solvents such as DMSO. The benefits of oil-free technology are numerous including ease-of maintenance and elimination of the cost of oil, oil filters, disposal of contaminated oil and pump rebuilds due to poor maintenance (i.e., “Who forgot to check the oil?”).

The initial cost of an oil pump can be less than an oil-free pump…an important buying consideration. However, over the life of the pump, oil-free technology is the most cost effective, low maintenance choice.

Question #6: What are your future application needs?

Think about not only your current application needs but those needs that you may have in the future. For example, if you are currently using only aqueous solvents but foresee the need in the future to use aggressive solvents, purchase a system that will allow you to do both.