Syntheses of xylan stearate nanoparticles with loading function from by-products of viscose fiber mills

A functional biopolymer was synthesized by introducing stearic acid (SA) to the backbone of xylan (X) obtained from viscose fiber mills. The SA–X derivatives were characterized by various tests for analysis of the functional properties. Effects on the esterification conditions including molar ratio, time and temperature were discussed, and the degree of substitution (DS) was in the range of 0.34–1.54. SA–X nanoparticles (SA–X NPs) were synthesized by dialysis, and the average particle size of the NPs was about 194 nm. Ketoprofen (KPF) was chosen as a hydrophobic model drug for the loading function evaluation, and the final encapsulation efficiency was about 64%. The KPF release profile in buffer standard solution with pH 11.0 and 2.0 were tested, and the final released amount were 43.6% and 53.8%, respectively. Thus, the fabrication of functional SA–X NPs provided a new way to improve the unreasonable application of factory biopolymer by-products.