Optimization and evaluation of cyclosporine A nanosuspension stabilized by combination stabilizers using high pressure homogenization method

The purpose of this study was to develop Cyclosporine A (CsA) nanosuspension by using different stabilizers for oral administration. CsA nanosuspension was prepared by high pressure homogenization technology and HPMC and Soluplus (R) combination were selected as stabilizers. After Design of Experiment (DoE) analysis, optimum formulation was selected and characterized by particle size (PS), particle size distribution (PDI) and zeta potential (ZP) measurements. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC), X-ray diffraction (X-RD), and fourier transform infrared (FTIR) analysis were also performed. Solubility studies were done with optimum lyophilised CsA nanosuspension. The results revealed that appropriate PS, PDI, and ZP results were not obtained with the use of stabilizers separately in preformulation studies. Optimum stabilizers ratio was determined CsA:HPMC:Soluplus (R) 1:1:0.5 (w/w) in nanosuspension formulation after DoE. It was found to be appropriate with a small particle size of 366.8 +/- 9.6 nm, a narrow particle size distribution of 0.48 +/- 0.02, and a negative zeta potential value of -14.4 +/- 0.4 mV after 30 homogenization cycles. In solubility study, the CsA solubility in the nanosuspension was increased up to 2.1 times in comparison with the coarse CsA. CsA nanosuspension showed a short-term stability over the examined period of one month. CsA nanosuspension can be successfully produced by Microfluidics with HPMC:Soluplus (R) combination as stabilizers using DoE approach.