High-throughput purification systems

Figure 6.3. Example chromatograms of two target compounds isolated by the high-throughput purification system shown in Figure 6.2. Chromatograms illustrate the performance of fast gradient analysis (ELSD and UV detector trace before purification). Reprinted with permission from reference 12.

At an early stage in the history of combinatorial synthesis it was apparent that product purity in excess of 80 % is not always attainable. In fact, purities of 30-40 % are quite common for several types of reaction. However, especially for single compounds from compound collections, high-throughput purification systems using HPLC have been developed. The degree of purity is first ascertained by analytical HPLC, and products having a purity below a pre-set threshold are subjected to this fully automated sample purification on a semipreparative or preparative scale. In first technical approaches, samples were... 

Yan, B. et al. High-throughput purification of combinatorial libraries I A high-throughput purification system using an accelerated retention window approach. J. Comb. Chem. 2004, 6, 255-261. 

Our group has established a high-throughput purification system based on the UV-triggered fraction collection technique. High-throughput parallel LC/MS technology is the foundation of our system due to its capacity to... 

Identification and purification of chemical compounds coming from the library are obviously a crucial step before their testing. Conventional methods had to be modified to efficiently apply to a large number of compounds. The important factors for identification, quantification, and purification include not only the separation power, but also a short amount of time and economy of the process. These demands lead to the development of high-throughput identification and high-throughput purification systems. 

Work up/purification procedures have also largely benefited from the commercial availability of semiautomated or automated instrumentation. The panel of tools spans from small, 96-well based devices to increase the throughput of manual operations (67, 68) to semiautomated systems able to purify in parallel combinatorial samples (69) or to concentrate in parallel large, discrete solution libraries (70, 71). Several systems developed in-house have also been recently rejxirted (72, 73), and a recent review covered the most recent trends in automated high-throughput purification methods for solution discrete libraries (74). 

Huher U. 2000. Semi-preparative purification of synthesis products with the Agilent high-throughput analysis system. Application Note. 

Searle, P Hochlowski, J. High Throughput Purification of Parallel Synthesis Samples An Integrated Preparative-LC/MS System with Quantitation by Chemiluminescent Nitrogen Detection, presented at The HPLC 2002, Montreal, Canada, June, 2002. 

Hochlowski, J. Searle, P. Gunawardana, G. Sowin, T Pan, J. Olson, J. Trumbull, J. Development and Application of a Preparative Scale Supercritical Fluid Chromatography System for High Throughput Purification, presented at Prep 2001, Washington, DC, May, 2001. 

Hochlowski J, Searle P, Gunawardana G, Sowin T, Pan J, Olson J, Trumbull J. Development and application of a preparative scale supercritical fluid chromatography system for high throughput purification. Presented at Prep 2001. Washington, DC, 2001. 

Figure 6.2. Schematic diagram of an LC/MS system for high-throughput purification of combinatorial library compounds using the MS signal as trigger for fraction collection. Reprinted with permission from reference 12.

Figure 35.12 shows a schematic diagram of an online high-throughput detection system for a reaction product synthesized by a microreactor. The system has a synthesis chip that a microreactor for the synthesis of 2,2,2-trifluore-A-phenetyl acetamide (TPA), an extraction chip for the purification of TPA from the reaction mixture, and an electrospray ionization mass spectrometer (ESl-MS) for... 

Many pharmaceutical companies possess high-throughput purification facilities, whose methodology can take the form of either a preliminary reaction cleanup or a high-performance technology. One such former technique is liquid-liquid extraction (LLE) as has been employed by workers at Procter and Gamble for the purification of their combinatorial libraries. This automated system partitions reaction mixtures between an aqueous and a water-immiscible pair of solvents in a microtiter format, and provides a typical 90% pure product with >85% recovery of desired material. Liquid-liquid extraction can also be accomplished by employing a solid... 

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