Formulation and evaluation of Flupirtine N-[2-amino-6-[(4-fluorophenyl)methylamino]-3- pyridinyl]carbamic acid ethyl ester nanosuspension by precipitation method

Flupirtine N-[2-amino-6-[(4-fluorophenyl)methylamino]-3-pyridinyl]carbamic acid ethyl ester nanosuspensions were prepared by precipitation method to accelerate the rate of dissolution. The formulations were constituted using different concentrations of Poloxamer, Tween 80, and Sodium Lauryl Sulfate. Using a scanning electron microscopy and Fourier transform infrared spectroscopy, the surface morphology and drug compatibility with other excipients of the formulated nanosuspensions were evaluated, respectively. The other physicochemical parameters such as solubility, particle charge (Zeta potential), particle size distribution, stability, and kinetic studies were determined. The nanosuspension particle size distribution with zeta potential was found to be positive. The drug content was within the range 93.7-102.23%. The entire nanosuspensions exhibited physical stability with no signs of settling. The formulation F8 nanosuspension prepared with Poloxamer 30 mg and PVP K30 60 mg exhibited promising enhanced saturation solubility up to 12.5 folds and increased dissolution (100.13%) as compared to pure Flupirtine (51.8%), which may help to improve bioavailability. Formulation F8 nanosuspensions showed enhanced dissolution and bioavailability.. KEYWORDS :Flupirtine, Nanosuspensions, Poloxamer, Saturation solubility, Zeta potential.