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In this article a simple method for automated pretreatment of chromatograms is presented. The resulting data matrix can be used as input for multivariate statistical analysis. Application of this method to high-performance anion-exchange chromatography-pulsed amperometric detection (HPAEC-PAD) chromatograms of honeys before canonical discriminant analysis results in very good performance in the data reduction with regard to the preservation of the original information content of the data. This pretreatment of the chromatogram allows for the use of all the peaks corresponding to the sugars present in the sample. This results in a high-quality discrimination between honeys of various types. A versatile program has been developed to apply this method. This serves as a starting point for software suited for food characterization and adulteration detection by semi-automatic pattern recognition applied to chromatographic analysis. 相似文献
395.
C16 modified and ground monolithic silica aerogel particles in submicrometer size, as a new type of stationary phase was prepared and integrated in polydimethylsiloxane (PDMS) microchip. The aerogel particles were packed into the microfluidic channel using a simple procedure, which does not require any special frit or fabrication step to retain the particles. The subnanoliter volume of samples can be transported through the porous, short length of packing with low pressure (< 3 bar). Food dyes as test components could be separated using low pressure within 6s. A 50-fold preconcentration could be achieved by retaining 100 nL volume of sample on the packing and elution with methanol. 相似文献
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红外光谱应用新进展及其与色谱指纹图谱对比分析 总被引:9,自引:5,他引:9
综述了红外光谱技术在常用中药材鉴定、地方民族药识别、中药炮制、中药注射剂四方面应用最新进展,这些包括加强计算机解析深度,增加药材前处理,利用二维相关红外光谱进行炮制监控等;另外,简述了色谱指纹图谱多组分含量分析框架体系的构建;分析比较红外光谱与色谱指纹图谱技术在中药质量控制领域应用的共性与差异点。 相似文献
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Fast separation of native proteins using sub‐2 µm nonporous silica particles in a chromatographic cake 下载免费PDF全文
A novel method for the fast separation of native proteins was investigated using sub‐2 µm nonporous silica packing inside a chromatographic cake having a diameter much larger than its thickness. Various silica‐based particles ranging from 630 nm to 1.2 µm were synthesized and chemically modified with polyethylene glycol 600. The packing material was laterally packed into a series of chromatographic cakes containing the same diameter (10 mm) and different thicknesses, ranging from 2 to 10 mm, and tested by hydrophobic interaction chromatography. The results showed that the sub‐2 µm NPS particles in a small chromatographic cake were found to have a high efficiency at a flow rate of 10 mL/min and a backpressure of <20 MPa. The effect of the thickness of the chromatographic cake on the resolution of the proteins was also investigated and it was found that too short a column length could dramatically decrease the protein resolution; the minimum column length was also qualitatively evaluated. The presented method is expected to be useful for routine analysis of native and/or intact proteins in hospitals and as a tool for the fast screening protein drugs and optimization of experimental laboratory conditions. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献