Preparation and Characterization of Poly-(methyl ethyl cyanoacrylate) Particles Containing 5-Aminosalicylic acid

Poly-(alkylcyanoacrylate) ester particles have been used for the preparation of different formulations ranging from ophthalmic delivery systems to cancer chemotherapy carriers in clinic. The aim of this study was to prepare and characterize poly-(methyl ethyl cyanoacrylate) (PMECA) particles containing 5-aminosalicylic acid (5-ASA). PMECA particles were prepared using the inverse emulsification polymerization technique. The effects of various formulation parameters such as dispersed phase volume, polymer to drug weight ratio, and surfactant concentration on loading efficiency and size of the prepared particles were investigated. The amount of drug was determined by UV spectrophotometery at 331 nm. Morphological characteristics of particles and particle size analysis were studied by Scanning Electron Microscopy (SEM) and Laser Light Scattering techniques, respectively. The results showed that there was no linear relationship between the dispersed phase volume (DPV) and loading efficiency of 5-ASA in the range of 20-50%. Increasing polymer/drug weight ratio in the range of 1-15, enhanced the loading efficiency from 11.4 to 78.2% in a linear mode (r=0.987). Increasing the surfactant concentration in the range of 1-3% did not increase the loading efficiency of the prepared particles, and increasing the concentration to 5% even decreased the loading efficiency of particles. Laser light scattering and SEM evaluations showed that in all prepared formulations, particles were in a mixture of micro and nanospheres and micro and nanocapsules and 50 percent of particles had mean sizes in the range of 6.4-10.1 micrometer. Although our results showed significant differences in the mean particle size between some of the prepared formulations, this variation was not practically important. It was concluded that by using proper conditions, it is possible to use PMECA as a polymeric matrix for loading of 5-ASA and the other hydrophilic drugs.