Iqbal Md Zafar, Novalin Senad
Department of Food Science & Technology, University of Natural Resources and Applied Life Sciences (BOKU), Muthgasse 18, A-1190 Vienna, Austria.
J Chromatogr A. 2009 Jun 26;1216(26):5116-21. doi: 10.1016/j.chroma.2009.04.065. Epub 2009 May 3.
Formose sugar and formaldehyde (HCHO) were analyzed using high-performance liquid chromatography (HPLC) utilizing a CarboPac PA1 column (Dionex) and pulsed amperometric detection. This HPLC system was unsuitable for the analysis of formose sugar and HCHO and thus reducing sugars and unconverted HCHO were determined by endowing them with charges through a derivatization method using 2,4-dinitrophenylhydrazine. The separation and detection of compounds were performed by three Chromolith RP-C18 columns (Merck) and diode array detection, at a wavelength of 360 nm ultraviolet light, respectively. Lower sugars (except HCHO) showed some instabilities when the derivatized samples were kept for the extended periods of time. For C(5) and consecutive higher sugars, a certain derivatization time was necessary. In the present case (formose reaction with partial HCHO conversion), approximately 18 h may be a reasonable compromise for the derivatization reaction. A derivatization agent to compound mole ratio of up to 100:1 was required to complete the derivatization of C(4) and higher sugars. However, the analysis of C(4) and consecutive higher sugars is problematic for example due to overlapping of peaks or branched-chain sugars.
使用配备CarboPac PA1柱（戴安公司）和脉冲安培检测的高效液相色谱法（HPLC）对福莫糖和甲醛（HCHO）进行分析。该HPLC系统不适用于福莫糖和HCHO的分析，因此通过使用2,4 - 二硝基苯肼的衍生化方法使还原糖和未转化的HCHO带电，从而对其进行测定。化合物的分离和检测分别通过三根默克公司的Chromolith RP - C18柱和二极管阵列检测进行，检测波长为360 nm紫外线。当衍生化样品长时间保存时，低级糖（除HCHO外）表现出一些不稳定性。对于C(5)糖及更高阶的糖，需要一定的衍生化时间。在当前情况下（福莫糖反应且部分HCHO转化），约18小时可能是衍生化反应的合理折中时间。完成C(4)糖及更高阶糖的衍生化需要衍生化剂与化合物的摩尔比高达100:1。然而，例如由于峰重叠或支链糖的原因，对C(4)糖及更高阶糖的分析存在问题。
