Stability study of OMP encapsulated PLA‐PLGA microparticles in simulated body fluid: a DLS perspective

In the present investigation outer membrane protein (OMP) from Vibrio cholerae were encapsulated successfully with poly‐lactic acid (PLA) and poly‐lactic glycolic acid (PLGA) microparticles by the double emulsion preparation technique. The prepared OMP‐PLA and OMP‐PLGA microparticles were characterised by scanning electron microscopy for observing their morphology and dynamic light scattering for their size, charge and poly dispersity index. The microparticles were further characterised by Fourier transmission infrared spectroscopy for observing the interaction of OMP antigens within the PLA and PLGA polymer matrix. The primary motive of the study was to observe the stability of the prepared microparticles when they are subjected to various pH ranges of 1.2, 6.8 and 7.2 with simulated body fluids for 30 days of incubation at body temperature. Both OMP‐PLA and OMP‐PLGA microparticles showed greater stability with pH 1.2 and 7.2 in the size and charge parameter scale with very marginal change in size and surface zeta potential. In the desired pH 6.8, the microparticles were degraded gradually up to the nanometre scale without affecting their surface zeta potential values. Thus, this present method can be a simple and cost‐effective approach for observing the stability measurement of pharmaceutical drugs.