Preparation Process Optimization and Stability Study of Loquat Flower Flavonoid Nanoparticles

In order to improve the stability of loquat flower flavonoids, loquat flower flavonoids/zein/pectin nanoparticles (LF/Z/P Nps) were prepared by anti-solvent precipitation method. Taking the embedding rate, particle size and Zeta potential as indicators, the effects of polysaccharide species, flavonoids concentration, zein concentration, alcohol-to-water ratio and pectin concentration on the preparation of nanoparticles were explored. The preparation process of nanoparticles was optimized by response surface experiment, and the characteristics of nanoparticles were studied. The results showed that the optimal preparation conditions were determined as follows: Loquat flower flavonoids concentration of 0.135 mg/mL, zein concentration of 2.2 mg/mL, alcohol-to-water ratio of 1:4, and pectin concentration of 0.78 mg/mL. Under these conditions, the embedding rate of nanoparticles was 86.20%±0.91%, the average particle size was 132.13±1.31 nm, the PDI was 0.16±0.01, and the Zeta potential was −33.97±1.46 mV. The nanoparticles were sensitive to pH and Na⁺, but could effectively maintain the antioxidant and stability of loquat flower flavonoids. In this study, LF/Z/P Nps with good stability were prepared by reverse-solvent precipitation method, which laid a certain theoretical basis for improving the processing adaptability of loquat flower flavonoids.