Separation of polyunsaturated fatty acids by selective inclusion in guanidinium-1,5-naphthalenedisulfonate-2-methoxyethanol host networks

• Published in: Biotechnology and bioengineering Vol. 92; no. 5; pp. 532 - 540
• Main Authors: Voogt, J.N, Blanch, H.W
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 05.12.2005; Wiley; Wiley Subscription Services, Inc
• Subjects: Absorption; Biological and medical sciences; Biotechnology; Chemical Fractionation - methods; Crystallization; Crystallization - methods; Esters; Fatty acids; Fatty Acids, Unsaturated - chemistry; Fatty Acids, Unsaturated - isolation & purification; Fundamental and applied biological sciences. Psychology; Guanidine - chemistry; Hydrogen Bonding; Hydrogen bonds; hydrogen-bonded networks; inclusion compounds; inclusion networks; Naphthalenesulfonates - chemistry; omega-3 fatty acids; polyunsaturated fatty acids; Porosity; separation; Solubility; Separation method; hydrogen- bonded networks; Hydrogen; polyunsaturated fatty acids; Polyunsaturated fatty acid; Selectivity; inclusion compounds; omega-3 fatty acids; n-3 fatty acid
• ISSN: 0006-3592; 1097-0290
• DOI: 10.1002/bit.20649

Hydrogen-bonded networks composed of guanidinium (G) and 1,5-naphthalenedisulfonate (NDS) have been developed for the selective inclusion and separation of fatty acid esters based on their degree of unsaturation. Porous crystalline networks have been synthesized and include fatty acid esters during crystallization from both methanol and 2-methoxyethanol. Crystalline networks formed in methanol are selective for the inclusion of saturates in preference to polyunsaturated fatty acid methyl esters, but their applicability is limited by the competing inclusion of the solvent methanol. In 2-methoxyethanol, a three-component host structure is formed that provides 4.1 x 4.7 angstrom2 pores which are also selective for saturated fatty acid ester inclusion. These networks do not suffer from the competing inclusion of the solvent 2-methoxyethanol as is the case with methanol, and thus complete removal of initial saturated fatty acid 2-methoxyethyl esters is possible. Binary selectivity experiments on mixtures of the 2-methoxyethyl esters of saturated stearic acid and the omega-3 fatty acid α-linolenic acid reveal that this three-component network structure provides nearly complete resolution of these two guests in the crystal and filtrate fractions. Separation of the 2-methoxyethyl esters of α-linolenic acid from the monounsaturated oleic acid is also possible, although with decreased efficiency in comparison to removal of the saturated fatty acid ester.