A recent solidification approach for nanosuspension: formulation, optimisation and evaluation of canagliflozin immediate release pellets

Abstract

Abstract Introduction: Canagliflozin is a BCS class IV drug. Nanosuspension is known to enhance the saturation solubility and dissolution rate of poorly soluble drugs owing to the increased surface area of nanosized particles. Aim: In the present study, we aimed to improve the dissolution characteristics of a poorly water-soluble drug canagliflozin by nanosuspension formulation and stability of this solubility enhancing system - nanosuspension can be improved by converting them into solidified forms as immediate release pellets. Materials and methods: Canagliflozin nanosuspension was formulated using the media milling method. Poloxamer 407 was used to stabilise nanosuspension. Prepared nanosuspensions were subjected to the characterisation of particle size, polydispersity index (PDI), and drug content. Optimised nanosuspension (NS1) was solidified by converting into immediate release pellets: as improved stability, where canagliflozin nanosuspension was used as a binder. Pellets were prepared by +extrusion-spheronization technique using microcrystalline cellulose (MCC) as pelletizing aid and sodium starch glycolate as super disintegrant. Different important process parameters e.g. concentration of sodium starch glycolate (A), spheronization speed (B) and spheronization time (C) were investigated by 23 factorial design to accomplish desired disintegration time (R1) and drug release at 10 min (R2). Results: The optimised nanosuspension had 120.5 nm particle size, 99.14% drug content and the optimised immediate release pellets (PF5) disintegrated within 23.29 second, and had 99.11% drug content. In vitro dissolution studies showed 89.59% drug release within 10 min in 0.75% w/v SLS. Scanning electron microscopy (SEM) confirmed uniform and spherically shaped pellets. Fourier transform infrared spectrometry (FTIR) and differential scanning calorimetry (DSC) analysis reveal no significant interaction between drug and excipients. Conclusions: It can be concluded from the findings of this study that the formulation of nanosuspension and its use as a binder in the formulation of immediate release pellets should be investigated further in order to improve the dissolution rate and formulation stability.