SBIR-STTR Award

The multilayer coil separator is a new device that efficiently and rapidly separates chemical mixtures by partitioning between two immiscible liquids. One liquid is immobilized within a coiled column of tubing while the second liquid is pumped through the column. The technique is complementary to other chromatographic systems and has the advantage of employing no solid phase, thereby eliminating losses by adsorption. It is particularly useful for preparative purification of polar and labile substances such as natural products, amino acids, and proteins.In Phase 1, a modified multicoil separator is being constructed to permit visual and photographic studies of the mixing behavior of the immiscible liquids within the column. This information will be used to design improved columns for the separator. Other studies will determine the shortest column that can be used to reliably predict the attainable resolution of a mixture using a particular solvent system, greatly reducing the time needed to find an optimum solvent system. A novel multilayer trough column will be evaluated to determine if it provides increased resolving power as would be expected from present and photographic studies on columns investigated in Phase 1. This phase of the project will include studies on new column designs and additional solvent systems, particularly some solvent systems that behave abnormally in multilayer coil separations. A major Phase 11 project will study the effect of temperature on solubility, partition coefficient, and phase retention. Phase 11 will achieve a significant goal of these studies, the construction of an apparatus operable at temperatures up to 500 Centigrade, which is expected to provide increased capacity and improved efficiency. In addition, a series of substances will be evaluated that will serve as standards to classify solvent systems used in countercurrent chromatography.National Cancer Institute

The multilayer coil separator is a new countercurrent chromatographic device for the efficient and rapid separation of chemical mixtures by means of partitioning between two immiscible liquids. The device has been commercially available for several years and is being increasingly applied to the isolation and purification of medicinally useful products of natural and synthetic origin. Its mild environment and the lack of adsorptive components make it especially useful for separation of biologically active substances. Although a wide range of solvents can be used, more viscous solvents behave erratically.An immediate goal of this research is to construct and test a heated countercurrent chromatograph, which will lower viscosity, promoting more uniform hydrodynamic behavior of the solvent, and which will double the capacity of the device by increasing solubility. A second goal is to improve the chromatographic efficiency of the coiled columns employed in the unit. To do this, the effect of several variations in column construction on efficiency and on the resolution of test substances will be measured with the aim of optimizing the geometry and physical structure of the columns. In the course of the work, valuable data on the properties of solvent systems will be obtained and published to benefit scientists who use this technology. Countercurrent chromatography facilitates separations of substances which were previously difficult to purify. It provides an improved method for purification of polar, water-soluble substances, and labile materials when used alone or as an adjunct to HPLC.Division of Research Resources (NCRR)