Synthesis and gelation ability assessment of amino acid derivative gelators

A series of amino acid derivative gelators based on carbonyl chloride with different carbon chain lengths were synthesized using L-alanine and L-phenylalanine as precursors. The structures of the products were verified by FT-IR, ¹H NMR and MS, respectively. In order to investigate the correlations between gelation ability and molecular structure, minimum gelation concentrations of organogelators and gel-sol transition temperatures of organogels were determined. The results indicated that: (i)these eight organogelators could produce gel in most oils; (ii)the increase of the amino acids chiral carbon atom steric hindrance and esterification degree of carboxylic acid group could lead to the decline of gelation ability; (iii)and the increase of carbon-chain length could strengthen the gelation ability. Overall, the relation between the gelator chemical structure and its gelation ability established during our work provides a theoretical basis for the development of a new organogel drug delivery system.