Fabrication Of Coenzyme Q₁₀/Copolymer Micelles With Modifided Casein By Malliard Reaction

Protein is widely available and safe raw materials for construction of nanocarriers used to deliver nutrients. However the solubility of protein is very poor at PI. In this case, the application of pretein as delivery systerm has been restricted to some extent. The objective of this work was to prepare casein-sextran copolymer (maillard reaction products) by ethanol injection and high pressure homogenization method. The determination of CoQ10 content in micelles was developed. Furthermore, the relationship between maillard reaction time and the properties of micelles was established. Finally, promicelles were prepared using freeze-drying in order to increase the properties of transport and widen thr scope of application.In this study, the recovery rate of CoQ10 from blank micelles ranged from (98.77±1.60)% to (95.90±0.80)% with conditions as follows:SDS concentration 0.31 mol/L, incubation temperature 30℃, sodium borohydride (7 mg/mL) 100μL, reduction time 3～5 min. The analysis of casein synchronous and exogenous pyrene fluorescence spectra indicated that the hydrophobic region of casein unit of copolymer was partly changed during solubilization at SDS concentration form 0 to 0.5 mol/L, so as to release CoQ10 at a high speed.The relationship between maillard reaction time arid encapsulation properties of copolymer micelles was studied. The z-average diameter of micelles was between 190 and 210 nm reacting for 4～24 h, presenting as spherical shape or ellipsoid. The stability and retention rate were higher of micelles with reaction time 20～24 h. Exogenous fluorescence spectra of pyrene showed that the sability of copolymer micelles was related to hydrophobic range. The stability of copolymer micelles was very well at pH 1～8. The major parameter for the stability of copolymer micells was not electrostatic exclusion interaction but steric effect from dexrean obtained from Zeta-potential and free amino analysis.Promicelles keeped a high stability during storage. in which CoQ10 exist as amorphous state from powder x-ray diffraction and differential scanning calorimetry analysis. After rehydration, the shap of micelles were similarly as primary ones and the z-average diameter increased at a little extent during storage. The reason was that dextran played as a protective reagent during freeze-drying.