Nanostructured Lipid Carrier of Propofol: a Promising Alternative to Marketed Soybean Oil-Based Nanoemulsion.

Nanostructured lipid carrier (NLC) of propofol was formulated using hot emulsification-probe sonication method for improvising its parenteral delivery by reducing pain on injection and risk of microbial contamination. The formulated NLC was optimized using central composite design and evaluated for particle size, zeta potential, morphology, free propofol concentration, hemocompatibility, stability, pain on injection, in vivo anesthetic activity, pharmacokinetics, and antimicrobial effectiveness in comparison to the marketed formulation. Optimized NLCs exhibited globule size, less than 200 nm, and zeta potential - 24.1 mV, indicating its stability. TEM images confirmed the spherical shape and nanosize (200 nm) of optimized NLCs. Free propofol concentration was also found to be 40% lesser than marketed formulation. Optimized NLC was found to be non-hemolytic. Rat paw-lick study showed that propofol NLC was significantly less painful compared to the marketed formulation. Anesthetic potential and pharmacokinetics of optimized NLCs were found to be similar to that of the marketed formulation. NLC was found stable in long-term storage under room temperature. Antimicrobial effectiveness study showed that propofol NLC suppressed microbial growth to a greater extent as compared to the marketed formulation. Hence, the developed propofol NLCs appeared to be clinically useful as a potential carrier for propofol delivery.