Construction Of Amphiphilic Cyclodextrin/Vitamin E Nanoparticle To Stabilize Picker Ing Emulsion

Cyclodextrins as well-known ?green? molecular hosts have been used in the fields of food and medicine due to its advantages such as cheap and easy acquisition and excellent biocompatibility.However,cyclodextrin does not have good emulsifying capacity because of its extreme hydrophilicity,which limits its application in food emulsification systems.In this paper,amphiphilic properties of cyclodextrins particles are modulated through esterification reaction between ?-cyclodextrins(?-CD)and octadecenyl succinic anhydride(ODSA)under alkaline conditions.Moreover,we aim to develop functional nanomaterials through loading Vitamin E by ODS-?-CD that can be used to extend the shelf life of the production and mimic the digestion of food effect in a predictable manner for achieving better-controlled,therapeutic release and response.The main results are listed as follows:Amphiphilic properties of cyclodextrins particles were modulated through esterification reaction between ?-cyclodextrins(?-CD)and octadecenyl succinic anhydride(ODSA)under alkaline conditions.ODS-?-CD particles with DS of 0.003,0.011 and 0.019 were obtained.The introduced hydrophobic long chain that was linked within ?-CD cavity led to the change of ODS-?-CD in terms of morphological structure,surface charge density,size and contact angle,upon which the properties and stability of the emulsions stabilized by ODS-?-CD were highly dependent.The average diameter of ODS-?-CD particles ranged from 449 nm to 1484 nm.With the DS increased from 0.003 to 0.019,the contact angle and absolute zeta potential value of these ODS-?-CD particles improved from 25.7° to 47.3°,48.1 to 62.8 mV,respectively.And the cage structure of ?-CD crystals was transformed to channel structure,then further to amorphous structure after the introducing of the octadecenyl succinylation chain.ODS-?-CD particles exhibited higher emulsifying ability compared to ?-CD.The resulting Pickering emulsions formed by ODS-?-CD particles were more stable during storage.The key in the health products and drug delivery areas is the shelf life of lipid-based colloidal products and its loaded accurate release of bioactive components.For that matter,the pH-response nanoparticle loaded with vitamin E(antioxidant)was synthesized successfully via simple esterification and co-precipitation approach in this study.The molecular structure of this dual-functional nanoparticle(ODS-?-CD-VE)was identified by NMR,FT-IR and XRD,that the tail chain of vitamin E was inserted in the cavity of ?-CD and the benzene ring head of vitamin E was complex with the hydrophobic chain of ODSA.The SEM,TEM and DLS illuminated ODS-?-CD-VE had typical diameters of 200 nm and wide flakes that were 80 nm thick and the perfect shape of the nanoparticle with uniform shapes and flat surfaces.The Zeta potential and contact angle of ODS-?-CD-VE showed that the Zeta potential decreased from +1.1mv to-47 mv,and contact angle reduced from 89.6° to 70.1°,as adjusting the pH from 2.0 to 7.0.This phenomenon indicated that the hydrophilic/hydrophobic of ODS-?-CD-VE was effective controlled by altering the pH.The results of oxidation stability showed ODS-?-CD-VE stabilized emulsion that was endowed more lasting antioxidation.Because the targeted accumulation of vitamin E,a model antioxidant,at the interface was achieved using the ODS-?-CD as interfacial vehicle,forming antioxidant shells around dispersed droplets.The results of simulated gastrointestinal tract found out that the bioactive components could be accurate release,that is,the emulsion stabilized by ODS-?-CD-VE resisted acidic hydrolysis and pepsin hydrolysis.And the bioactive components could be released effectively as the interface layer of emulsion was thinning as coming into intestinal juice.It was beneficial to the contact between enzyme and substrate and enhanced the digestibility of emulsion.This research opens up promising ways to deliver drugs or functional foods.