Abstract
Purpose :
Nanoparticles have promise for front of the eye drug delivery but to be successful should have a method of increasing their residence time in the front of the eye and be able to degrade once they are in the body so that they can be eliminated. The goal of the research performed was to synthesize novel nanoparticles that display, based on in-vitro preliminary studies, mucoadhesive and degradable properties.
Methods :
Nanoparticle synthesis was conducted through suspension polymerization with 2-hydroxyethyl methacrylate (HEMA), ethylene glycol dimethacrylate (EGDMA) or N,N’-bis(acryloyl)cystamine (BAC), 3-(acrylamido)phenylboronic acid (PBA), methacrylic acid (MAA), benzoyl peroxide (BPO), sodium dodecyl sulfate (SDS), 1-butanol, and milliQ water. The composition amounts were altered to observe the impact on nanoparticle size. The average effective diameter of the nanoparticles was obtained using dynamic light scattering. BAC was selected as an alternative crosslinker to modify the degradability of the nanoparticles. Release profiles of dexamethasone from nanoparticles were determined through high pressure liquid chromatography and UV detection at a wavelength of 254 nm. Degradation studies were performed by the addition of 10 mM dl-dithiothreitol (DTT) solution to previously synthesized nanoparticle solutions followed by shaking incubation at 37C. Transmission electron microscopy (TEM) was used to observe the morphology and degradation of the nanoparticles. Mucoadhesion tests were conducted with bovine submaxillary mucin and quantified by zeta potential analysis.
Results :
The average effective nanoparticle diameters found for the poly(HEMA) nanoparticles crosslinked with EGDMA were 97.83 nm ± 0.46 nm to 125.50 nm ± 0.89 nm. The use of BAC as a crosslinker resulted in average effective diameters within the range of 200 nm to 300 nm. Images from TEM confirmed the presence of spherical nano sized particles that degrade in the presence of DTT. Preliminary tests using zeta potential analysis showed a decrease in surface charge of 11.25 mV ± 1.67 mV when nanoparticles (1 mg/mL) containing PBA were incubated with mucin (0.56 mg/mL).
Conclusions :
The results presented display that novel nanoparticles with mucoadhesive and degradable characteristics were synthesized. Further experimentation to be conducted includes in vitro cell studies and more in depth mucoadhesion studies.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.