Preparation And Properties Of Rutin Loaded Nanostructured Lipid Carrier

The nanostructured lipid carrier(NLC)is a novel encapsulation carrier,which utilizes the defect structure formed by the solid oil in the process of cooling and crystallization to encapsulate the active substance,and the use of the liquid oil increases the formation of the defect structure,thereby increasing the load of the active substance.The nanostructured lipid carrier has good biocompatibility and simple preparation process,and therefore,it is widely used in the fields of medicine,food and cosmetics.Rutin is a natural flavonoid compound with various functions such as anti-inflammatory,anti-oxidation and sun protection,but its further application is limited due to poor solubility and stability.This study aims to improve the solubility and stability of Rutin by encapsulating carrier technology,and further improve its application in sunscreen cosmetics.Firstly,Rutin loaded nanostructured lipid carrier was prepared by emulsion-ultrasonic method.The encapsulation of Rutin was 0.1% and the encapsulation efficiency was 90%.The solubility and stability of Rutin were improved by encapsulation.The particle size,polydispersity coefficient and encapsulation efficiency were taken as indicators.The optimal preparation process was determined by single factor experiment.The emulsification temperature was 85°C,the homogenization power was 16000 rpm,the ultrasonic power was 225 W,the ultrasonic time was 5 min,and the cooling method was ice bath cooling.Under the optimal preparation process,the effect of formula composition on the performance of Rutin loaded nanostructured lipid carrier was investigated.Through the compatibility test,propylene glycol was selected as the "media" for Rutin to enter the oil phase.The triglyceride caprylate and the tetradecyl myristate were used as the liquid grease and solid oil for preparing Rutin nanostructured lipid carrier.Fatty alcohol polyoxyethylene ether-21 and Fatty alcohol polyoxyethylene ether-2 are used as emulsifiers.By single factor investigation,the optimal formulation was determined to be 4% tetradecyl myristate,6% caprylic acid triglyceride,4% propylene glycol,3% Fatty alcohol polyoxyethylene ether-21 and 0.8% Fatty alcohol polyoxyethylene ether-2.Rutin nanostructured lipid carrier was prepared by the optimal preparation process and formulation,and its encapsulation ability for different content of rutin was investigated.The results showed that the encapsulation content was increased from 0.1% to 0.5%,encapsulation efficiency form 89.3% fell to 42.3%,and therefore,the ability of nanostructured lipid carriers to encapsulate Rutin was limited.In order to further improve the encapsulation ability of the nanostructured lipid carrier to Rutin,a microencapsulated Rutin nanostructured lipid carrier composite carrier was prepared by using modifier.The hydroxypropyl-?-cyclodextrin was selected as a modifier for the microencapsulated nanostructured lipid carrier by investigation of particle size,encapsulation efficiency,room temperature storage stability and UV absorption performance.Through single factor investigation,the optimum pH of the system was determined to be 6.14,and the content of sodium chloride was 0.7%.It was found that the hydroxypropyl-?-cyclodextrin content plays an important role in the encapsulation performance of the microencapsulated Rutin nanostructured lipid carrier.Further research by UV spectrophotometer,rotary oscillatory rheometer and in vitro sustained release experiment,it found that the ultraviolet absorption properties,sustained release properties,and viscosity of microencapsulation of Rutin nanostructured lipid carrier are all improved with the increase of hydroxypropyl-?-cyclodextrin content.Finally,it was concluded by microscopy,scanning electron microscopy and differential scanning calorimetry that the structure and formation mechanism of microencapsulated Rutin nanostructured lipid carrier maybe the forming of hydrogen bond between hydroxypropyl-?-cyclodextrin and nanostructured lipid.The microencapsulated nanostructured lipid carrier prepared by using the optimum inorganic salt and hydroxypropyl-?-cyclodextrin content at the optimal pH can increase the loading of Rutin from 0.1% to 1%.The rate is maintained above 80%,with good sustained release properties,sun protection and usability.The microencapsulated nanostructured lipid carrier technology effectively improves the solubility and stability of Rutin and improves its application performance in sunscreen cosmetics.