Removal of Triolein Lipid From Aqueous System by Molecularly Imprinted Chitosan and Its Derivative

Chitosan was molecularly imprinted to remove triolein (a model lipid triacylglyceride) from water. Molecularly-imprinted chitosan (chitosan-MIP) was synthesized by crosslinking it with glutaraldehyde in the presence of triolein as the template at 50°C for 2h. MIPs of octanoyl derivative of chitosan(Oct-MIP) were also prepared by similar method. Octanoyl chitosan was synthesized by N-acylation of chitosan using octanoyl chloride at room temperature for 12h. Contact angle measurements of water droplet on chitosan and octanoyl chitosan revealed increased hydrophobicity of octanoyl derivative of chitosan. FTIR spectroscopy was used to characterize the derivative and the MIPs. All the synthesized polymers. Oct-MIP and chitosan-MIP could imprint approximately 77% and 66% of triolein template, respectively. Binding experiments revealed that Oct-MIP exhibit higher triolein binding capacity than corresponding non-acylated polymers. In 6h, 1mg of Oct-MIP and chitosan-MIP could rebind 534.50µg and 380.35µg of triolein respectively. Non Imprinted octanoyl chitosan and chitosan bound 272µg and 198.24µg triolein respectively. Both types of MIPs could also bind a triolein analog (1,3-dioleoyl-2-palmitoyl glycerol).

1-(2-Hydroxyphenyl)octan-1-one

The title compound, C14H20O2, was synthesized by the reaction of phenol and octanoyl chloride. All non-H atoms are coplanar, with an r.m.s. deviation of 0.031 Å. In the crystal structure, molecules are linked into chains along the a axis by intermolecular C—H...O hydrogen bonds.