Development of novel amisulpride-loaded liquid self-nanoemulsifying drug delivery systems via dual tackling of its solubility and intestinal permeability.

OBJECTIVE: The aim of the current investigation was at enhancing the oral biopharmaceutical behavior; solubility and intestinal permeability of amisulpride (AMS) via development of liquid self-nanoemulsifying drug delivery systems (L-SNEDDS) containing bioenhancing excipients.

METHODS: The components of L-SNEDDS were identified via solubility studies and emulsification efficiency tests, and ternary phase diagrams were constructed to identify the efficient self-emulsification regions. The formulated systems were assessed for their thermodynamic stability, globule size, self-emulsification time, optical clarity and in vitro drug release. Ex vivo evaluation using non-everted gut sac technique was adopted for uncovering the permeability enhancing effect of the formulated systems.

RESULTS: The optimum formulations were composed of different ratios of Capryol™ 90 as an oil phase, Cremophor® RH40 as a surfactant, and Transcutol® HP as a co-surfactant. All tested formulations were thermodynamically stable with globule sizes ranging from 13.74 to 29.19 nm and emulsification time not exceeding 1 min, indicating the formation of homogenous stable nanoemulsions. In vitro drug release showed significant enhancement from L-SNEDDS formulations compared to aqueous drug suspension. Optimized L-SNEDDS showed significantly higher intestinal permeation compared to plain drug solution with nearly 1.6-2.9 folds increase in the apparent permeability coefficient as demonstrated by the ex vivo studies.

CONCLUSIONS: The present study proved that AMS could be successfully incorporated into L-SNEDDS for improved dissolution and intestinal permeation leading to enhanced oral delivery.