Continuous-flow encapsulation of ketoprofen in copolymer microbeads via co-axial microfluidic device: Influence of operating and material parameters on drug carrier properties

Microchannels based microfluidic systems are able to obtain monodispersed microparticles but are limited by cost, time and channel clogging. We succeeded in on the fly encapsulation of high ketoprofen contents in acrylate-based copolymer microbeads by environment friendly UV induced free radical polymerization in off-the-shelf co-axial microfluidic device. FTIR shows complete polymerization of acrylate monomers and interaction between carboxylic group of ketoprofen and ester group of monomers. DSC and XRD confirm amorphous nature of drug in microbeads. Different comonomer content formulations show limited drug release at low pH, a helpful properties to avoid gastric irritating effect of ketoprofen associated with conventional dosage forms. At pH 6.8 microbeads release higher content of drug by a non-Fickian diffusion mechanism. Their drug release rate depends upon the weight content of ethyl acrylate in the formulation as well as their size, increasing by increasing the former and decreasing the later. (C) 2012 Elsevier B.V. All rights reserved.