Abstract: Based on the traditional pretreatment technique,semi-micro-pretreatment and micro-pretreatment methods of sugar and sugar alcohol were set up respectively.Gas chromatography and mass spectrometry(GC-MS) were used to analyze the derived products.The results showed that the derived sugars and sugar alcohols from the same sample pretreated with the above-mentioned three methods are nearly the same in gradients and contents.However,compared with the above-mentioned traditional method,the amounts of extraction solvent and derivation solvent used in the other two methods greatly decrease and the time and labour consumed by the other two methods also obviously reduce.The amount of solvent consumed by micro-pretreatment technique is 1/200 to 1/100 of that by traditional pretreatment and the time for pretreatment is decreased above 5 times.Compared with the traditional method,liquid-liquid microextraction(LLME) is economical,fast and convenient.

Key words: LLME, micro-derivation, sugar, sugar alcohol, GC-MS, capillary