Abstract: | Poly (hydroxy ethyl methyl acrylate-co-acrylic acid) pH sensitive microspheres crosslinked with N,N′-Methylenebisacrylamide were prepared by free radical emulsion polymerization. Different formulations was prepared by varying amounts of 2-hydroxy ethyl methacrylate (HEMA) acrylic acid (AA) and N,N′-Methylenebisacrylamide (NNMBA), Triprolidine hydrochloride (TPH), and hypertensive drug was loaded during in situ polymerization and in vitro release studies was performed at 37°C. DSC analysis reveals that the drug is molecularly dispersed in the microspheres. SEM studies indicate the formation of microspheres with smooth surface and spherical shape. The in vitro release studies of the microspheres were carried out in pH 1.2 and 7.4 media. |