The thermo-WELL microplate has been recently developed by the British company Pharmaceutical Technology Ltd. as a simple and economic solution to temperature controlled reactions in the laboratory. As such, the device meets the requirement for medium sample throughput. Designed to allow flexibility, thermo-WELL is a low cost option to synthesis and other temperature controlled processes, such as biological reactions, analysis and sample preparation. In addition to ensuring excellent temperature control and uniformity across the unit, the inlet-outlet connectors equally allow multiple units to be linked in series for increased sample capacity.
The combinatorial approach to the synthesis of new drug entities has stimulated the development of a huge variety of technologies for parallel processing. These have ranged from simple heated agitation systems to fully automated multi-probe synthesizers. Many have been designed to meet the demand for new drug candidates, but the drive towards parallel processing in all areas of laboratory research has expanded in a similarly substantial way. For most of the laboratories however, sophisticated technologies are not always necessary. Often, only the need exists for the synthesis of sufficient material to meet the requirements of the next process step or scale up. In this case, the laboratory team might be better off with a simpler apparatus than the expensive devices which are commonly sold in this area, in order to gain a greater flexibility and control.
Exactly for this purpose, thermo-WELL has been designed as a simple 24-well microplate for sample volumes up to 4.0 ml. The device is sealed at its base and fitted with two valve-controlled inlets/outlets to be connected to a circulating heater/cooler unit for temperature control. The valve-controlled inlet/outlets are self-sealing on disconnection from the fluidics system, allowing the units to be moved for other process steps, such as evaporation, purification as well as analysis. Manufactured from polypropylene, this unit is compatible with a wide range of solvents, acids and bases. The microplate operates across the temperature range -30∞ to 80∞ C.
Used as a single stand-alone unit, thermo-WELL is able to handle up to 24 reaction or process steps. If, for instance, five units are connected in series, 120 process steps can be carried out in parallel, each with reaction volumes up to 4.0 ml. The thermo-WELL unit however can be incorporated into three other instruments, which are an agitator, an autosampler and a solid-phase "workstation" for adaptation to a range of different requirements. Up to five thermo-WELLS can be integrated into the wellplate-AGITATOR to perform temperature controlled/agitated reactions. If a company requires a higher capacity, Pharmaceutical Technology will design a customized system.In addition, the wellplate-AGITATOR has also been developed for use with the programmable random access intelligent auto-SAMPLER, which allows the automation of liquid sampling and agitation steps. If necessary, different temperatures can be applied within several thermo-WELL devices. The third technology, the thermo-WELL unit can take part in, constitutes duo-PREP. This is a solid-phase process "workstation", based on moving cartridges containing the solid-phase bed. Process areas in which duo-PREP is applied, include extraction and purification. The duo-PREP workstation accommodates two thermo-WELL units, allowing extraction or clean-up of synthesized compounds or other process products present in the wells of the unit.
The duo-PREP process is carried out using the duo-PREP Operator together with duo-PREP cartridges and the thermo-WELLS. During this process, an array of cartridges are lowered into the array wells within a multi-well unit. As the cartridges descent, an outer flexible seal engages with the inner wall of the well, generating a pocket of air above the solution. Once the cartridge inlet enters the process solution, the liquid is forced upwards, through the solid-phase bed and into the cartridge. It is during this step that the solid-phase process takes place. Whenever the cartridge is withdrawn, the seal engagement with the well creates a partial vacuum on the underside, which "pulls" the solution back into the well. As such, duo-PREP can provide the extraction or purification of solutions present in the thermo-WELL unit.
The thermo-WELL unit presents itself as far more than just a temperature control microplate in the way that it is perfectly suitable for a comprehensive range of requirements in the laboratory. Pharmaceutical Technology Ltd. has provided the technical data for this article.