Stabilization of Etoricoxib Nanosuspension Using Acacia chundra Gum and Copolymers: Preparation, Characterization, and In Vitro Cytotoxic Study.

Present communication deals with the stabilization of etoricoxib nanosuspension using Acacia chundra gum and its acrylamide-grafted and carboxymethylated copolymers. Acrylamide grafting and carboxymethylation of A. chundra gum were carried out and synthesized copolymers were characterized. Ultrasound-assisted solvent-antisolvent method was utilized to co-precipitate the stabilizers over etoricoxib nanoprecipitates. A 32 full factorial design was used to evaluate the effect of independent variables, that is, the concentration of drug and stabilizer over the dependent variables, that is, particle size (PS), and entrapment efficiency (EE%) of nanoparticles. The effect of process parameters over super saturation, nucleation, and PS were studied and the role of mixing and ultrasound radiation was correlated. FTIR, DSC, and 1H NMR analysis showed a significant difference between the copolymers. The application of stabilizers leads to the synthesis of small, spherical, no aggregated, and composite nanoparticles. PS growth analysis after 45 days showed no sign of "Ostwald repining" and aggregation. Optimized formulations prepared using A. chundra gum (formulation K9), acrylamide-grafted (formulation A8), and carboxymethylated (formulation C1) copolymers showed t80% in 190, 270, and 170 min, respectively. Cytotoxic studies showed that the formulation A8 had better control over cell growth than the pure drug against MCF-7 cell line. The results indicated that the A. chundra gum and its acrylamide and carboxymethylated copolymers can be easily synthesized and utilized for the fabrication of stabilized nanosuspension.