Degradation and Stability of PBCA and POCA Nanoparticles
Nanoparticles represent promising carriers for controlled drug delivery. In this project three
different intruments: Zetasizer, Nanosight and Gas Chromatography, have been used to detect and analyse degradation of monodisperse poly butylcyanoacrylate (PBCA) and poly
octylcyanoacrylate (POCA) nanoparticles with a mean size diameter of 145 and 155 nm,
respectively. It was found that the Nanosight and Gas Chromatography are valuable instruments
for detecting and analysing degradation, whereas the Zetasizer turned out to give
unreliable results because of increasing polydispersity in the samples. PBCA and POCA
particles were tested in two different setups. One including a dialysis setup in room temperature,
in which the solvent was regularly exchanged. The other consisted of reagent bottles
held in an oven at 37C. In the dialysis method the influence of buffers with pH 4.0, pH
5.5 and pH 7.4 were tested. In the reagent bottles different mediums were tested, like cell
medium, blood serum and buffer pH 7.4 with and without the enzyme esterase. From these
experiments it became clear that PBCA particles degraded significantly faster than POCA
particles in all tested mediums. Degradation of PBCA particles were also strongly affected
by the pH. At pH 4.0 there was little (10%) or no degradation still after 30 days. The concentration of PBCA particles in pH 7.4 decayed as a 1/x -function, in which 53\% of the PBCA particles in buffer pH 7.4 have been degraded after 8.5 hours.
The degradation-rate for PBCA and POCA in blood serum was approximately similar as in buffer pH 7.4, whereas in cell medium it was slightly slower.
Place, publisher, year, edition, pages
Institutt for fysikk , 2013. , 105 p.
IdentifiersURN: urn:nbn:no:ntnu:diva-22417Local ID: ntnudaim:9932OAI: oai:DiVA.org:ntnu-22417DiVA: diva2:649661
Davies, Catharina de Lange, ProfessorMørch, Yrr