About 610 mg (3.34 mole) of lysine was dissolved in 50 ml of distilled water. Additionally, 1.0 gram (1.67 mole) of ceftriaxone was dissolved in 50 ml of a separate volume of distilled water. The solution containing arginine was adjusted with 1N-HCl until the solution reached pH 6.0. The ceftriaxone solution was then added to the lysine solution and stirred by a magnetic stirrer at room temperature for 1 hour forming a ceftriaxone-lysine solution. To the ceftriaxone-lysine solution was added about 400 mg of carrageenan and the solution was stirred by magnetic stirrer at room temperature for 2 hours. A ceftriaxone-lysine-carrageenan hydrogel was formed. The hydrogel was then freeze-dried while in the swollen state, yielding about 1.92 g of the freeze-dried complex.
