治療糖尿病之phenformin (芬法敏)由於使用後會造成乳酸中毒，行政院衛生署雖已於民國 67 年即禁用，然卻於某大陸藥品中檢出，因而引起我們研究的興趣。本研究係以氣相層析質譜儀定該成分，續以高效液相層析儀分析其含量。氣相層析質譜儀設定條件如下：HP-5MS 毛細氣相層析管， 以 70eV 離子電能作電子撞擊式 (EI mode) 分析， 起始溫度100 ℃維持 3 分鐘，再以每分鐘 10 ℃之升溫速率，至 280 ℃並維持 15 分鐘。高效液相層析分析條件如下：Cosmosil 5C18 AR (5 cm × 4.6 mm) 及μ Bondpak phenyl (30cm ×3.9 mm) 為分析之管柱， 使用移動相為磷酸二氫鉀 (pH 6.55)： 乙?? (40：60)。 流速 1mL/min，偵測波長 235 nm。以 metformin 為內部標準品。分析結果如下：同日間及異日間之測試，其相對標準偏差在 1.6 ％以下。偵測極限及最低檢出量分別為 0.065 μ g/mL 及0.20 μ g/mL，添加回收率 102.7 ％，檢體中平均含量為 3.45mg ╱膠囊。

　　　　　Phenformin was prohibited by the ROC Department of Health in 1978. Inthis investigation, a GC-MS was used for the detection of phenformin in herbalpreparation produced in Mainland China followed by determination by HPLC. ForGC-MS, a HP-5MS capillary column was used. The initial column temperature was at100 ℃ for 2 min, ramping 10 ℃ /min to 280 ℃, then holding at 280 ℃ for 15min. Ionization source temperature was at 230 ℃, and 70 eV electron impact modewas employed. HPLC was performed on a Cosmsil 5C18 AR (5 cm × 4.6 mm), and a μBondpak phenyl (30 cm × 3.9 mm)column using 0.01M potassium dihydrogenphosphate(pH 6.55)-ace- tonitrile (60:40, v/v) as eluent, with flow rate at 1.0 mL/minand detection wavelength set at 235 nm. Metformin was used as the internalstandard. The interday and intraday precisions were less than 1.6%. The limit ofdetection and the limit of quantitation were 0.065 μ g/mL and 0.20 μ g/mL,respectively, The spike recovery was 102.7%. The average content of phenforminin the preparation was 3.45 mag per capsule.