Research on self-assembly micelles of N-(4-methylimidazole)-hydroxyethyl-chitosan loading quercetin / 中国药科大学学报

To improve the solubility of quercetin ( QT) , one of flavonoids that can inhibit the proliferation of vari-ous types of cancer cells, the novel amphiphilic polymer N-( 4-methylimidazole)-hydroxyethyl-chitosan ( MHC) , synthetized by chemical derivatization from chitosan, was used as the self-assembly micelles of QT. The formed polymer was characterized by 1 H NMR, elemental analysis and pyrene fluorescence spectrometry. The formulation of MHC micelles loading quercetin was optimized through single factor experiment. Then the optimized formulation was obtained as follows:the concentration of MHC was 0. 67% and the ratio of drug and carrier was 1 ∶10. The micelles particle size was ( 99. 21 ± 1. 71) nm, Zeta potential was +( 20. 01 ± 0. 72) mV and drug loading was ( 5. 42 ± 0. 32 )%. The in vitro release curve was investigated and was found to conform to Higuchi equation of Q=0. 1101 t1/2 -0. 064. The results of in vivo experiment showed that the mean rentention time and bioavail-ability of the MHC-QT micelles were 21. 42 h and 57. 49 μg h/mL, respectively, compared to 0. 30 h and 2. 50 μg h/mL of the free QT solution. These indicated that the MHC micelles could significantly improve the solubility of QT, the drug sustained-release effect and bioavailability, which would used as carrier for the anti-tumor drugs.

Detemination of 4-Methylimidazol in soy sauce by capillary gas chromatography / 中国法医学杂志

Objective A method for the determination of 4-methylimidazole in soy sauce by capillary gas chromatography was studies.Methods The method consisted of a methylene chloride to elution,followed by concentration of the eluate.N,N-Dimethylaniline(IS) was added in and GC analysis of the eluate,prior to GC analysis.The GC analysis was carried out by DB-FFAP capillary column and nitrogen phosphorus detector(NPD).Results The linear range was 4.9mg~1.5?102 mg/L and the limit of detection was 0.16 ug/L.The average recoveries were 97.25%and 99.44% by stand addition method in 0.0102mg and 0.0602mg 4-methylimidazole.Conclusion The method was simple,rapid and sensitive.A useful method for determining 4-methylimidazole in soy sauce was provided for forensic analysis.