本研究利用固相微萃取 (solid-phase microextraction, SPME) 與氣相層析質譜儀之結合，建立尿中.喃甲酸 (.喃甲醛之尿中代謝物) 與肌酸酐的分析技術，以提供評估.喃甲醛暴露之生物偵測工具。有關尿中.喃甲酸的量測，本研究先以鹼性水解的方式，將結合態的.喃甲酸 (furoic acid-glycine conjugate) 轉為自由態 (free furoic acid)，接著再以65μm poly (dimethylsiloxane)/divinylbenzene (PDMS/DVB) 的固相微萃取纖維於電磁攪拌轉速 1200 rpm 下，以直接樣本接觸方式吸附60秒後，以氣相層析質譜儀進行分析。有關尿中肌酸酐的量測，首先亦使用65μm PDMS/DVB纖維，在電磁攪拌轉速 1200 rpm 下以直接樣本接觸方式吸附60秒後，將已吸附肌酸酐的纖維挪至裝有100 μL無水三氟醋酸的4 mL樣本瓶中頂空吸附30 sec，再將纖維挪至另一個空白的樣本瓶並靜置10 min (以利衍生物trifluoroacetamide的生成)，最後再以氣相層析質譜儀進行分析。另外，本研究亦測試包括：溫度、攪拌速度、及含鹽量等不同因素對纖維吸附量的影響。本研究針對尿中.喃甲酸與肌酸酐所分別建立之分析方法，分析準確度皆在100±10％以內，而偵測極限則為 0.0077 g L-1 (.喃甲酸)、及0.13 g L-1 (肌酸酐)。與現有方法相比較，本研究能有效縮短樣本前處理及分析時間並減少溶劑的使用，且與肌酸酐現有分析方法的平行比對亦具有一致性。

The solid-phase microextraction (SPME) technique was evaluated for the determination of furoic acid and creatinine in urine. For furoic acid, the alkaline hydrolysis step was first performed to hydrolyze the furoic acid-glycine conjugate to free furoic acid. Afterwards, the poly (dimethylsiloxane)/divinylbenzene (PDMS/DVB) fiber was used with direct urine sample immersed for 60 sec under 1200 rpm magnetic stirring. Analysis with gas chromatography/mass spectrometry (GC/MS) was followed. For the determination of creatinine, the PDMS/DVB fiber was aslo directly immersed into urine sample for 60 sec under 1200 rpm magnetic stirring. Then the fiber was transferred to a 4 mL vial which was filled with 100 μL of trifluoroacetic anhydride (TFAA) and stood 30 sec for headspace extraction. Afterward the fiber was transferred again to another blank 4 mL vial and stood 10 min for on-fiber derivatization before the analysis with GC/MS. The absorption-time profiles for both furoic acid and creatinine were examined. The precision, accuracy and method detection limits (MDLs) were evaluated. The relative standard deviations were less than 10% and the accuracy were 100±10% for both furoic acid and creatinine. With 2 mL of urine sample, MDLs were 0.0077 and 0.13 g L-1 for furoic acid and creatinine, respectively. Compared with other techniques, the study shown here provided a simple, fast and reliable method for the analysis of furoic acid and creatinine in urine.