反相高效液相色谱法测定3种中成药中的葛根素

 建立了测定小儿清感灵片、步长新脑心通胶囊和感冒清热颗粒 3种中成药中葛根素含量的反相高效液相色谱方法。采用APEXODS色谱柱 ,以醋酸铵缓冲液 (10 0mmol/L ,pH 5 0 ) 甲醇 (体积比为 75∶2 5 )的混合溶液为流动相 ,检测波长为 2 5 0nm ,流速为 0 8mL/min。葛根素在 2mg/L～ 2 0mg/L时其色谱峰面积与质量浓度的线性关系良好 (r =0 9999) ;上述 3种中成药中的葛根素含量分别为 3 48mg/g ,1 0 8mg/ g及 1 5 2mg/ g(蔗糖型 ) ;其加样回收率分别为 99 0 % ,93 4%和 97 5 %。该法简便、快速、专属性强 ,可以作为多种中药制剂中葛根素含量的测定方法。     

CZE法鉴别测定苦豆草药材中多种生物碱成分

建立了一种同时在苦参药材中鉴别9种生物碱并测定其中6种生物碱含量的毛细管区带电泳法.即用未涂渍熔融石英毛细管柱50μm×41.5cm(有效长度33cm),以0.3mol/L Tris水溶液一正丙醇(ⅥV=60/40,pH=7.0)为运行缓冲液,氯丙那林为内标,在检测波长210nm、运行电压30kV、50mbar压力下进样10s、运行温度25℃和分析时间40min进行毛细管区带电泳.结果表明,宁夏市售苦豆草中含有野靛碱、莱蔓碱、槐安碱、苦参碱、槐定碱、槐果碱、苦豆碱、氧化槐果碱和氧化苦参碱,其中苦参碱、槐果碱、苦豆碱、氧化槐果碱和氧化苦参碱的含量接近,槐定碱的含量明显高于它们.本法灵敏、准确、专属性好,适用于苦豆草药材中生物碱成分的鉴别和含量测定.     

Rate-oriented perceptual image coding using contrast-based quantization

<正>A new image coding approach is proposed by controlling the quantization step via minimizing the perceptual distortions(in terms of image's contrast measurement).The proposed method is a rate-oriented contrast-based approach,which is in contrast to the conventional quality-oriented contrast-based image coding.The algorithm achieves a higher perceptual quality performance against several methods developed previously.