Preparation and characterization of biopolymer nanoparticles based on lactoferrin-polysaccharide complexes

Optimal weight ratios for the preparation of lactoferrin (LF), N-succinyl chitosan (SCh) and galactomannan (GM)-based polyelectrolyte complexes (PEC) were determined. Soluble PEC were obtained using solutions of biopolymers: lactoferrin (2 mg/ml), N-succinyl chitosan (8 mg/ml) and galactomannan (16 mg/ml) in 0.15 M NaCl, pH 6.5 ± 0.1, under normal conditions at a weight ratio of 1:1 1:2 and 1:3 LF:GM; 1:1, 1:2, 1:3 and 1:4 LF:SCh; 1:3:2 and 1:2:3 LF:SCh:GM. Using the method of heat treatment below the temperature of protein denaturation from the soluble complexes were formed stable biopolymer particles which have size characteristics of 250-400 nm, regular spherical shape, a negative zeta potential of 12-17 mV and good storage stability. The load of lactoferrin in the particles was 76-87%. Yield of freeze dried particles was 70-80%. The obtained particles could eventually be used for the targeted transport of biologically active substances.