Reaction #985267

Reaction equation

HEMA

FITC

→

FITC

methacrylic acid

Solvents

water

Conditions

Workup

1. 1
   OtherThus, particles were produced of approximately 40 nm diameter
2. 2
   Otherwas prepared
3. 3
   Otherwas removed
4. 4
   Concentrationremaining in solution from the original solution concentration
5. 5
   WashThe aggregate was washed with five 10 mL aliquots until the washings
6. 6
   Otherwas placed in 21 mL of phosphate buffered saline (PBS, pH 7.4, NaCl concentration=120 mmol/L) at 37° C.
7. 7
   OtherPeriodic aliquots were removed

Procedure

The rate of release of a macromolecule trapped in the voids between hydrogel particles in an aggregate can be controlled by modifying the ionic character of the particles. Thus, particles were produced of approximately 40 nm diameter using 90:10 HEMA:MAA. A solution of 1 mg/mL of FITC-BSA in a suspension of 60 mg/ml hydrated copolymer nanoparticles in 20 mL milli-Q water was prepared. The solution/suspension was spun in a centrifuge at 50,000×G for 1 hr at room temperature. The resulting aggregate, which was yellow, was removed and the percent loading was determined by subtracting the FITC-BSA remaining in solution from the original solution concentration. The loading of this aggregate was calculated to be approximately 7% by weight. The aggregate was washed with five 10 mL aliquots until the washings contained no further FITC BSA as determined by UV-Visible spectroscopy. The aggregate (2.1 g) was placed in 21 mL of phosphate buffered saline (PBS, pH 7.4, NaCl concentration=120 mmol/L) at 37° C. and was shaken at 60 cycles per second on an orbital shaker. Periodic aliquots were removed and analyzed by UV-Visible spectroscopy. FIG. 11 shows the release of FITC-BSA from the aggregate over time. Variations in the mole percent methacrylic acid in the hydrogel particles of the aggregate result in distinct changes in the rate of FITC-BSA release.

Source