Synthesis and characterization of amphiphilic block copolymer of poly (L-phenylalanine)-b-poly(L-aspartic acid) / 国际药学研究杂志

Objective To design and synthesize a different molecular mass block copolymer of poly(L-phenylalanine)-b-poly (L-aspartic acid)(PPA-PAA). Methods The L-phenylalanine and L-aspartic acid were used as raw materials to synthesize L-phenyl?alanine N-carboxy-ɑ-amino acid anhydride and L-aspartic acid-β-benzylester N-carboxy-ɑ-amino acid anhydride. The target com?pounds of amphiphilic block copolymer of PPA-PAA were synthesized by ring-opening polymerization. The critical micelle concentra?tion of the amphiphilic polymer was determined by pyrene fluorescence probe method. Results The copolymers of hydrophobic chain segment 500,2000,and 4000 were synthesized and the structures were confirmed by hydrogen nuclear magnetic resonance and Fouri?er transformed infrared. The critical micelle concentration of polymers changed with adjusting the feed ratio of PPA to PAA. Conclu?sion The results show that the longer the hydrophobic chain segment of PPA is,the smaller the critical micelle concentration of poly?mers. The results lay the groundwork for further studying the stabilizing effect of the drug polymer nanoparticles with different proper?ties.

Digitized fingerprints of Panax Ginseng rubra by HPLC / 中成药

AIM: To establish a HPLC digitized fingerprints of Panax Ginseng rubra to control its quality. METHODS: The chromatographic fingerprints were determined by injecting 20 ?L of the sample solution each time on a Century SIL C_ 18 AQ column (20 cm?4.6 mm, 5 ?m) with the gradient elution solvent system composed of 0.1 mol/L NaH_2PO_4 aqueous solution-acetonitrile. The flow rate was 1 mL/min, the column temperature was maintained at (30?0.15)℃ and the signals were acquired at 203 nm. The chromatographic fingerprints were evaluated by both the chromatographic fingerprint index (F) and the information index of chromatographic fingerprint (I) and so on. RESULTS: 30 co-possessing peaks were selected as the fingerprint peaks and the similarities between each of the ten batches and the referential chromatographic fingerprints of Panax Ginseng rubra were calculated while taking adenosine peak as the reference peak. CONCLUSION: This method with good characteristics and specificity can be used in the quality control of Panax Ginseng rubra.

The fingerprints of Fructus Gardeniae by HPCE / 中成药

AIM: A capillary electrophoresis fingerprints(CEFP) method of Fructus Gardeniae was established to evaluate its quality. METHODS: The background electrolyte(BGE) was 25 mmol/L sodium borate solution containing 10% acetonitrile.The detection wavelength was 228 nm and 24 kV was applied.Fructus Gardeniae was extracted by water and injectded for 15 s(9 cm).Some parameters were used to evaluate the similarities.(RESULTS): 24 co-possessing peaks were selected as the fingerprint peaks of Fructus Gardeniae taking chlorogenic acid peak as the reference peak.The similarities between each of the ten places and the standard CEFP of Fructus Gardeniae were evaluated both qualitatively and quantitatively.The CEFP was also evaluated by the information index(I) and the relative information index(I_r). CONCLUSIONS: The CEFP has acceptable precision,reproducibility and can be used to control the quality of Fructus Gardeniae.

Determination of chlorogenic acid and caffeic acid in Shegan Kangbingdu Injection by RP-HPLC / 中成药

AIM: To develope a reversed-phase high performance liquid chromatographic method for the quantitative determination of chlorogenic acid and caffeic acid in Shegan Kangbingdu Injection. METHODS: The operation was carried out in the Kromasil ODS column with the mobile phase consisting of a mixture of water-methanol-acetonitril aceti acid(95∶10∶5∶2,v/v),in which the flow rate of 1.0 mL/min and UV detection wavelength at 326 nm were set to determine the contents of chlorogenic acid and caffeic acid. RESULTS: There were good linear relations between the concentrations and the peak-areas of chlorogenic acid and caffeic acid.The relative standard deviation of peak areas for chlorogenic acid or caffeic acid were 0.60%,0.32%,respectively.The two kinds of standard solutions were both stable in 16 h(RSD=0.54% for CGA,0.11% for CFA).The average recovery was 100.1%,99.6% for CGA,CFA,repectively.The detectable limit(S/N=3)was 0.012,0.020 mg/L,and the quantitative limit (S/N=10) was 0.037,0.052 mg/L,repectively. CONCLUSION:The method is simple,sensitive,rapid and accurate,and can be used for the quality control of Shegan Kangbingdu Injection