Development, characterisation and evaluation of supersaturated triglyceride free drug delivery (s-TFDDS) of lornoxicam.

The present work was aimed at formulating a supersaturated triglyceride free drug delivery system (s-TFDDS) of lornoxicam and evaluating its in vitro and in vivo potential. s-TFDDS contain the drug above its saturation solubility and consists of a hydrophilic surfactant, a hydrophobic surfactant, solubiliser and pH modifier. D-optimal mixture experimental design was applied to optimise s-TFDDS. Three formulation variables, X 1 (Tween 20®), the surfactant X 2 (Capryl PGMC®) and X 3 (Transcutol P), were included in the design. The systems were assessed for light transmittance and solubility of lornoxicam. The values of optimised formulation components (X 1, X 2 and X 3) were 60.0, 10.0 and 30.0 %, respectively. The combination of components was optimised for maximum solubilisation capacity of lornoxicam by combined effect of pH and temperature. The optimised liquid preconcentrate was evaluated for particle size (small-angle neutron scattering study), robustness to precipitation, effect of polymer on precipitation inhibition and by in vitro dissolution. The liquid preconcentrate was adsorbed on solid carrier (Neusilin US2, Sylysia 320) and characterised by in vitro dissolution, X-ray diffraction, differential scanning calorimetry and scanning electron microscopy study. An increase in dissolution (DE15min, 100 %) in simulated gastric fluid at pH 1.2 was achieved without precipitation of lornoxicam. Spectral characterisation reveals no sign of lornoxicam precipitation on solid carriers. Comparative pharmacodynamic evaluation was investigated in terms of anti-inflammatory efficacy using a rat paw oedema model in rats. The s-TFDDS formulation showed the maximum percent inhibition of oedema as compared with plain and micronised lornoxicam.