A method for detecting metformin suitable for small amount of sample is disclosed. The method includes the following steps. A sample including metformin is provided. Extracting metformin in the sample by mixing the sample, the organic extractant and an alkaline and obtaining an extract. The extract and a matrix are co-crystallized, the co-crystallized mixture is fired by a laser beam to form a vaporized ion, and the vaporized ion is analyzed to obtain a value of metformin.一種二甲雙胍檢測方法,係適用於少量之待測樣品,其包含:提供一待測樣品;混合該待測樣品、一有機萃取溶劑及一鹼液,使該有機萃取溶劑萃取該待測樣品所含有之二甲雙胍,以獲得一萃取液,其中,該鹼液為一飽和之氫氧化鈉水溶液;及使該萃取液與一基質形成一結晶狀固態物,以一雷射光束離子化該結晶狀固態物中的二甲雙胍,使二甲雙胍形成一氣相離子,並以一質荷比分析器檢測該氣相離子,以獲得一二甲雙胍強度值。S1‧‧‧樣品提供步驟S2‧‧‧萃取步驟S3‧‧‧分析步驟
