Nano-engineering of sertraline liposomes using supercritical fluid and optimization of the involved parameters

Sertraline is one of the drugs whose transport from the blood circulation to the brain is severely limited by the blood-brain barrier and it shows low bioavailability (44%). Liposomes can be an effective carrier for this drug and increase bioavailability. In this study, the synthesis of nanometer-sized liposomes containing sertraline hydrochloride is proposed using a technique called supercritical fluid expansion into aqueous solution (ESSAS). In this technique, phospholipid precipitation rates are controlled, and homogeneous liposomes with nanometer-sized dimensions can be created. The operational parameters were optimized using the response surface methodology (pressure drop: 29.9 MPa, collection time: 13.6 min, temperature: 40 °C), which showed that the optimal values for the encapsulation efficiency, mean size, and number of liposomes were 78.4%, 89.5 nm, and 85, respectively. Also, the drug release test showed that it takes 27 h for sertraline to be completely released from the liposomal suspension.