Buffer Synthesis Lab Report
Preparation of buffer solutions
1. Activation buffer
(Mixed Phosphate Buffer, pH 5.5)
Solution 1: An accurately weighed quantity of 1.61 g of potassium dihydrogen phosphate was dissolved in sufficient deionized water to produce 100 mL of solution.
Solution 2: An accurately weighed quantity of 35.81 g of disodium hydrogen phosphate was dissolved in sufficient volume of deionized water to produce 100 mL.
Accurately measured volume of 96.4 mL of solution 1 was mixed with 3.6 mL of solution 2 to get the activation buffer.
2. Coupling buffer (pH 8.2-8.35)
An accurately weighed quantity of 0.42 g of sodium hydrogen carbonate was dissolved in 50 mL of deionized water to obtain the coupling buffer.
3. Storage buffer
(Phosphate buffer saline, pH 7.4) …show more content…
5.4. Synthesis of Poly L-Lactide (PLA)
PLA was synthesized by the ring opening polymerization of L-Lactide in presence of stannous octoate. L-Lactide (1.44 g (0.01 mol)) was dissolved in 20 mL of toluene; 1.5 mg of stannous octoate was added to this solution. The mixture was refluxed under continuous stream of nitrogen at 110ºC for 12 h. A white product was obtained. The product was dissolved in 15 mL of chloroform and an excess of cold ether (~32 mL) was added to the solution. The polymer precipitated as a white solid. It was washed with methanol, dried in desiccator and stored protected from light.
The polymer was characterized by NMR and IR …show more content…
Effect of surfactant.
The stability of the nanoparticles largely depends on the type and concentration of the surfactant(s) used.
5.5.1.1. Effect of different surfactants
Three batches of nanoparticles each were prepared with different surfactants (Pluronic F 68 and PVA) and their effect on particle size, entrapment efficiency and yield was observed (Table 5.1).
PLA (20 mg) was dissolved in 2 mL of DCM and 1 mg of FU was dissolved separately in deionized water. The solution of FU was added under sonication to the PLA solution and the mixture was sonicated further for 3 min. The resulting primary water-in-oil emulsion was added slowly through fine syringe to a continuously sonicated 0.5% w/v aqueous solution of Pluronic F-68 or PVA over a period of 25 min. The water-in-oil-in-water emulsion obtained was stirred on a magnetic stirrer for 6 h at room temperature to remove DCM and complete the nanoparticle formation. The nanoparticles were washed thrice with deionized water to remove any non-encapsulated drug through ultracentrifugation at 16000 rpm (25180g) for 30 min at
1. Activation buffer
(Mixed Phosphate Buffer, pH 5.5)
Solution 1: An accurately weighed quantity of 1.61 g of potassium dihydrogen phosphate was dissolved in sufficient deionized water to produce 100 mL of solution.
Solution 2: An accurately weighed quantity of 35.81 g of disodium hydrogen phosphate was dissolved in sufficient volume of deionized water to produce 100 mL.
Accurately measured volume of 96.4 mL of solution 1 was mixed with 3.6 mL of solution 2 to get the activation buffer.
2. Coupling buffer (pH 8.2-8.35)
An accurately weighed quantity of 0.42 g of sodium hydrogen carbonate was dissolved in 50 mL of deionized water to obtain the coupling buffer.
3. Storage buffer
(Phosphate buffer saline, pH 7.4) …show more content…
5.4. Synthesis of Poly L-Lactide (PLA)
PLA was synthesized by the ring opening polymerization of L-Lactide in presence of stannous octoate. L-Lactide (1.44 g (0.01 mol)) was dissolved in 20 mL of toluene; 1.5 mg of stannous octoate was added to this solution. The mixture was refluxed under continuous stream of nitrogen at 110ºC for 12 h. A white product was obtained. The product was dissolved in 15 mL of chloroform and an excess of cold ether (~32 mL) was added to the solution. The polymer precipitated as a white solid. It was washed with methanol, dried in desiccator and stored protected from light.
The polymer was characterized by NMR and IR …show more content…
Effect of surfactant.
The stability of the nanoparticles largely depends on the type and concentration of the surfactant(s) used.
5.5.1.1. Effect of different surfactants
Three batches of nanoparticles each were prepared with different surfactants (Pluronic F 68 and PVA) and their effect on particle size, entrapment efficiency and yield was observed (Table 5.1).
PLA (20 mg) was dissolved in 2 mL of DCM and 1 mg of FU was dissolved separately in deionized water. The solution of FU was added under sonication to the PLA solution and the mixture was sonicated further for 3 min. The resulting primary water-in-oil emulsion was added slowly through fine syringe to a continuously sonicated 0.5% w/v aqueous solution of Pluronic F-68 or PVA over a period of 25 min. The water-in-oil-in-water emulsion obtained was stirred on a magnetic stirrer for 6 h at room temperature to remove DCM and complete the nanoparticle formation. The nanoparticles were washed thrice with deionized water to remove any non-encapsulated drug through ultracentrifugation at 16000 rpm (25180g) for 30 min at