The Research Of Intestinal Lymphatic Absorption Of Curcumin Based Self-emulsifying Drug Delivery System

Curcumin has many biological activities such as anti-inflammatory、antioxidant and antitumor.However,the bioavailability is very low in plasma after oral administration because of its poor solubility and bad cytomembrane penetrability and tachymetabolism,also because of the liver first pass effect.It is difficult to apply at clinic for curcumin which was Biopharmaceutics classification system IV(BCS IV).ObjectiveThis paper aims to develop an optimizational oral formulation of curcumin based self emulsifying drug delivery system( SMEDDS) according to the physicochemical properties and biological properties of curcumin combined with intestinal lymphatic system drug absorption characteristics,for ameliorating the bioavailability of curcumin as well as avoiding first pass effect in hepar though the novel way.Methods1 The study on physicochemical properties of curcumin and preparation of SMEDDS:(1) A supersaturated solution of centrifugal method was using for the determination of curcumin in water, MCT and IPM;(2) Content determination of curcumin in vitro medium was analyzed by HPLC and validated the method;(3) With the study of pseudo three component phase diagrams for SMEDDS of different ratio preparation, transparent microemulsion was as an index to screening emulsifying ability,descriptions and proportion of different materials;(4) Based on the content and particle size as the evaluation index, the stability of curcumin SMEDDS was evaluated preliminarily.2 Research on biology of SMEDDS:(1)Adult male SD rat was selected for intragastric administration of different preparations and blood was taken from the tailvein in specified time.After removing protein and enrichment process the plasma samples were detected by LC-MS.(2) By using DAS3.0 software, the pharmacokinetic parameters were calculated, and thepharmacokinetic parameters were analyzed.3 To study the absorption of intestinal lymphatic pathway system:( 1)Chylomicrons blocked animal model was established by intraperitoneal injection of cycloheximide,for a comparative study absorption mechanism of SMEDDS tending to intestinal lymphatic system.Results(1)The experiment results show that the solubility of curcumin in medium chain fatty acids(MCT), polyethylene glycol 400(PEG400),Cremophor EL and Cremophor RH40 has preferable solubility, the solubility is respectively:5395.29±297.29、65404.77±2482.92、1954.40±75.56、1895.63±35.56 μg/m L.(2)The method of HPLC has high sensitivity and high specificity,and specificity experiment found that the chosen excipients would not influence analysis of curcumin.The method has good linear in the 1.9125~122μg/m L range, sample recovery rate is above 93%, which could meet the test requirements.(3)The pseudo three component phase diagrams found,MCT as oil phase, PEG-400 as assistant emulsifier, Cremophor RH40 as emulsifier,the formulation with maximum emulsifying capacity.MCT:PEG-400:Cremophor RH40 =2: 2: 6(w/w), as every 1 g SMEDDS containing 30 mg curcumin, the diameter of the emulsion,19.3 + 2.7 nm, was minimum, and exhibited a single peak, and the dosage of emulsifier was suitable.(4)Curcumin SMEDDS at 4 ℃ and 25 ℃ storage conditions for 14 days, the content of the samples and the particle size variety was small, that curcumin SMEDDS was stable in 14 days at least.(5)The method,multiple reaction monitoring(MRM),was determined by specificity experiment, and identified the retention time of curcumin and hesperetin which was internalstandard. Curcumin detection nuclear mass ratio was m/z 177�'m/z 177 and hesperetin was m/z 152.9�'m/z 152.9.The analysis would not be interfered by the blood impurity.The range of linear was 8.83 to 2260 ng/m L,so that the trace curcumin in plasma can be detected.Also the rate of recovery and extraction recovery can meet the experiment requirements.(6)Pharmacokinetic parameters analysis by unilateral and bilateral t test indicate that AUC0-∞ and Cmax of three preparations has statistical difference(P ≤0.05).The AUC0-t and Cmax value of curcumin SMEDDS was 1280.05ng/L*h、368.38 ng/L;curcumin MCT suspension was 934.893 ng/L*h、229.355 ng/L;curcumin water suspension was 239.235 ng/L*h、102.608 ng/L.(7)By intraperitoneal injection of cycloheximide 3 mg/kg, a rat chylomicron obstruction model was established.The AUC0-t and Cmax result of curcumin SMEDDS was 224.956 ng/L*h、127.568 ng/L;curcumin MCT suspension was 887.893 ng/L*h、231.353 ng/L.Conclusions(1)Emulsifier type and dosage of SMEDDS have great influence on particle size of the formation of microemulsion in water, and the prepared SMEDDS has good stability.(2)The establishment of LC-MS determination method for curcumin concentration in plasma was good repeatable and accurate which met the requirement.The detection limit was 4.41 ng / ml,which satisfied the determination of need.(3)For normal rats the biological utilization of Curcumin SMEDDS is obviously higher than that of MCT suspension formulation, which was 2.15 times of the latter. SMEDDS can obviously improve the bioavailability of curcumin.(4)Chylomicron obstruction animal model Pharmacokinetic studies show that, the main absorption route of SMEDDS is through the intestinal lymphatic pathway transporting curcumin into circulation in order to increasing the curcumin absorption.