Preparation of Poly(butyl cyanoacrylate) Nanoparticles by Aqueous Dispersion Polymerisation in the Presence of Insulin

Butyl cyanoacrylate has been polymerised by dispersion in acidified water, with introduction of insulin during the reaction, to yield nanoparticles containing the drug. Polymer molecular weight measurement, carried out by gel permeation chromatography, shows that insulin is capable of initiating polymerisation of this monomer, but if the drug is included at the beginning of the synthesis the reaction is not controllable and nanoparticles are not formed. Introduction of insulin into a dispersed monomer system that has already been initiated by the hydroxyl ion, but is still polymerising, gives a controllable synthesis yielding nanoparticles. Molecular weight measurement suggests that the insulin is covalently bound to the polymer chain.