Development and Optimization of Amlodipine besylate microspheres by 3-factor–3–level Box-Behnken design

The current study set out to assess the impact of microsphere formulation variables on the drug release and entrapment efficiency of a model medication, amlodipine besylate. A three-factor, three-level Box-Behnken design was used to examine the main and interaction impacts of several independent formulation factors, including the ratio of drug to polymer, the concentration of surfactant, and the amount of acetone. Entrapment efficiency (EE) and cumulative percentage drug release (CPR) were the dependent variables. In order to maximise amlodipine entrapment efficiency and provide a desirable, sustained release over a 12-hour period, formulation optimisation was done. The drug release, entrapment efficiency, size, and shape of the prepared microspheres were evaluated. To explain the effect of all components and their co-linearities on the %EE and CPR of amlodipine, respectively, mathematical relationships were obtained: EE = 78.95 –1.67A+3.18B +1.50C and CPR = +81.75 –7.72A +5.15B +0.9500C +2.68AB –0.1100AC –0.1800BC –11.79A2 –1.14B2 –0.1775C2 (r2 = 0.9970). A new batch was made using the optimised formulation, and there was a strong agreement between the observed and expected values of CPR and EE. We were able to understand the effect of formulation parameters on the entrapment efficiency and obtain optimal and sustained drug dissolving through the use of the Box-Behnken experimental design.