Formulation of self-nanoemulsifying drug delivery systems containing monoacyl phosphatidylcholine and Kolliphor^(■) RH40 using experimental design

The development of self-nanoemulsifying drug delivery systems(SNEDDS) to enhance the oral bioavailability of lipophilic drugs is usually based on traditional one-factor-at-a-time approaches. These approaches may be inadequate to analyse the effect of each excipient and their potential interactions on the emulsion droplet size formed when dispersing the SNEDDS in an aqueous environment. The current study investigates the emulsion droplet sizes formed from SNEDDS containing different levels of the natural surfactant monoacyl phosphatidylcholine to reduce the concentration of the synthetic surfactant polyoxyl 40 hydrogenated castor oil(Kolliphor ~? RH40). Monoacyl phosphatidylcholine was used in the form of Lipoid S LPC 80(LPC, containing approximately 80% monoacyl phosphatidylcholine, 13% phosphatidylcholine and 4% concomitant components). The investigated SNEDDS comprised of long-chain or medium-chain glycerides(40% to 75%), Kolliphor ~? RH40(5% to 55%), LPC(0 to 40%) and ethanol(0 to 10%). D-optimal design, multiple linear regression, and partial least square regression were used to screen different SNEDDS within the investigated excipient ranges and to analyse the effect of each excipient on the resulting droplet size of the dispersed SNEDDS measured by dynamic light scattering. All investigated formulations formed nano-emulsions with droplet sizes from about 20 to 200 nm. The use of mediumchain glycerides was more likely to result in smaller and more monodisperse droplet sizes compared to the use of long-chain glycerides. Kolliphor~? RH40 exhibited the most significant effect on reducing the emulsion droplet sizes. Increasing LPC concentration increased the emulsion droplet sizes, possibly because of the reduction of Kolliphor~? RH40 concentration. A higher concentration of ethanol resulted in an insignificant reduction of the emulsion droplet size. The study provides different ternary diagrams of SNEDDS containing LPC and Kolliphor ~? RH40 as a reference for formulation developers.

Exploring the utility of the Chasing Principle:influence of drug-free SNEDDS composition on solubilization of carvedilol, cinnarizine and R3040 in aqueous suspension

This study assessed the influence of the composition of drug-free SNEDDS co-dosed with aqueous suspensions of carvedilol(CAR), cinnarizine(CIN) or R3040 on drug solubilization in a twocompartment in vitro lipolysis model. Correlation of drug log P or solubility in SNEDDS with drug solubilization during in vitro lipolysis in the presence of drug-free SNEDDS was assessed. SNEDDS with varying ratios of soybean oil:Maisine 35-1(1:1, w/w) and Kolliphor RH40, with ethanol at 10%(w/w) were used. SNEDDS were named F65, F55 and F20(numbers refer to the percentage of lipids) and aqueous suspensions without drug-free SNEDDS(F0) were also analyzed. While the ranking order of drug solubilization was F65? F55? F204F0 for CAR; F65? F554F204F0 for CIN and F65? F55? F204F0 for R3040-with higher CAR solubilization than for R3040 and CIN-the ranking of S_(eq)of CAR, CIN and R3040 in SNEDDS was F65 o F55o F20, F65? F554F20 and F654F554F20, respectively. Therefore, the composition of SNEDDS influenced the solubilization of CIN, but not CAR and R3040. Furthermore, high S_(eq) in SNEDDS did not reflect high drug solubilization. As CAR(log P 3.8) showed higher solubilization than CIN(log P 5.8) and R3040(log P 10.4), a correlation between drug log P and drug solubilization was observed.