Synthesis of Pur-CS Nanoparticles

Sodium TPP and CS were separately weighed to 1000 mg in a 10 mL volumetric flask, diluted to volume with water, and then left to dissolve in the refrigerator for 6 h or more. Next, 10 mg of Pur was ultrasonically dissolved in 5 mL of a 5% ethanol aqueous solution, and 100 mg of laboratory-made CS was dissolved in water to make a 2.0 mg/mL solution. The pH of CS solution was adjusted to 4.5 with 1% dilute hydrochloric acid and saturated sodium hydroxide. Then, 6 mL of the CS solution was transferred into a beaker and placed under a magnetic stirrer. Next, 5 mL of the Pur ethanol solution was slowly dripped into the CS solution, then added to the mixture at 500 r/min for 30 min. After the stirring was completed, 1 mL of a 0.6 mg/mL TPP solution was accurately weighed and slowly dropped into a mixed solution of Pur and CS. After all of the additions, stirring was continued for 30 min at a speed of 500 r/min until the system showed significant opalescence.